Method of coloring hair with washfast yellow imidazolium direct dye compounds

ABSTRACT

Described herein is a method of dyeing the hair. The method includes applying to the hair a hair color composition including one or more direct dye compounds and rinsing the hair with water. The one or more direct dye compounds each include a yellow chromophore, one or two permanent cations, one to four incipient cations, and one or more hydrophobic moieties. The incipient cations are pendant to the core structure and are neutral. The one or more direct dye compounds enter the hair shaft after the hair color composition is applied to the hair. The hair color composition has a pH of from about 7 to about 11. The pH of the hair after rinsing is from about 3.5 to about 6. The rinsing of the hair causes one or more of the one to four incipient cations to change from neutral to positively charged inside of the hair shaft.

TECHNICAL FIELD OF THE INVENTION

Provided is a method of dyeing the hair and other keratinaceous materialwith one or more stable, washfast yellow imidazolium azo direct dyecompounds. The direct dye compounds each have one to four incipientcations. A decrease in pH when rinsing the hair causes one or more ofthe incipient cations to change from neutral to positively chargedinside of the hair shaft. Also described herein are hair colorcompositions comprising the imidazolium azo compounds that may serve ashair dyes, and methods of using the same. These materials can be usedwith or without oxidant.

BACKGROUND OF THE INVENTION

In general, direct dye products last only 6-10 shampoos and are henceknown as semi-permanent. However, many consumers want more permanentresults, and therefore default to oxidative dye products that containhydrogen peroxide or other oxidants. Providing vibrant violet-blue toblue colors is challenging, because many of the vibrant dyes are notsufficiently stable for permanent haircolor compositions, and those thatare stable to hair dyeing conditions are not sufficiently vibrant. Thedirect dye compounds and the method described herein can be used ineither direct dye or oxidation dye products.

The permanent alteration of the color of keratinous fibers, inparticular human hair, by the application of hair dyes is well known. Inorder to provide the consumer with the shade, longevity, and theintensity of color desired, an oxidative coloring process involvingcomplex chemical reactions is utilized. Permanent hair dyeingformulations typically comprise primary intermediates (also known asoxidative hair dye precursors or developers) and couplers (also known ascolor modifiers or secondary intermediates). These dye precursors aresufficiently small, polar and soluble to diffuse into the hair shaftwhere, once activated by an oxidizing agent under basic conditions, suchas hydrogen peroxide, the primary intermediates react with other dyeprecursors, e.g., couplers, to form larger colored chromophores in thehair shaft. The chromophores formed in the hair shaft do not readilydiffuse out of the hair during subsequent washing with water and/ordetergents because they are bigger, less polar and soluble than dyeprecursors that diffused in.

Hair colorant products are typically sold in the form of kits containinga dye component (e.g., a dye solution) and an oxidizing component (e.g.,a hydrogen peroxide solution). In use, the dye component is mixed withthe oxidizing component and the resultant mixture is applied to hair.When the two components are mixed, oxidizing agents present in theoxidizing component begins to oxidize primary intermediates present inthe dye component and the oxidized primary intermediates begin to reactwith couplers to form chromophores. Since coloring hair is one of thebeauty routines, it is highly desirable that the dyeing process,excluding bleaching, be rather a physical process, which would allow itto be aligned with many other beauty routines such as applying lip colorand facial touchups. The challenge is to still meet all of the otherrequirements of hair color (e.g., washfastness, resistance toperspiration, little or no bleeding of color from the hair when it iswet, evenness, etc.).

Many attempts have been made by the hair color industry to enhance thewashfastness of direct dyes by either forming a covalent bond betweenchromophore and proteins inside hair or increasing the number of bindingsites, typically cationic centers, on the chromophore. However, eachattempt has its drawbacks. The approach through covalent bonding doesnot differentiate proteins in hair from skin. The approach throughmultiple binding sites on the dyes (i.e. multiple positive charges tointeract with negative sites on hair, either by bonding severalmonocationic dyes together or by installing multiple cationic centers ona single chromophore) runs into the obstacles of uneven color due touneven damage (negative charges) along the length of the hair fibers andreduced dye penetration into hair fibers because the dyes are typicallyat least twice as large as common oxidative dye precursors. An increasein the number of binding sites minimizes bleeding and color loss causedby rinsing by providing stronger hair-chromophore interactions. However,the same strong binding force to the cuticle also prevents thechromophores from penetrating deep into the cortex of hair, because itis difficult for dyes with multiple positive charges to diffuse throughnegatively charged networks of keratin proteins. Additionally, sincepolycationic dyes remain bound to the hair surface rather thanpenetrating into the fiber, it is difficult to produce dark shades, dueto limited binding sites on the surface of hair.

In dye chemistry, use of heterocyclic components in the chromophoreleads to pure, intense colors. Pure, intense yellows are particularlyimportant in hair dyeing, because they are necessary to deliverattractive gold and warm shades that are rich and brilliant rather thanmuted, as when less pure colors are used. They not only are needed foradding brightness, but they also can be used to give the appearance oflightening. For yellow direct dyes, one of the challenges is that somethe heterocyclic moieties in dyes, such as thiazolium and pyridinium canbe unstable under in-use conditions, particularly in the presence ofoxidants like hydrogen peroxide.

Accordingly, there is a need for a direct dye compound with improvedwashfastness without the drawbacks previously described, and theseimidazolium azo dyes meet all the criteria of color, stability, andfastness to be used as permanent hair dye compounds.

SUMMARY OF THE INVENTION

Described herein is a method of dyeing fibers, particularly keratinfibers, and most particularly hair, with yellow azo chromophores basedon a combination of an imidazolium group as the acceptor portion and anN-substituted-5-aminopyrazole as the donor portion of the molecule, themethod comprising (a) applying to the hair a hair color compositioncomprising one or more yellow direct dye compounds, the one or moredirect dye compounds each comprising (i) a yellow chromophore; and (ii)one or two permanent cations, wherein the permanent cations are part ofthe chromophore, and wherein the chromophore and the permanent cationsform a core structure; (iii) one to three incipient cations, wherein theincipient cations are pendant to the core structure, and wherein theincipient cations are neutral; and (iv) optionally one or more C2-C9hydrophobic moieties, wherein the one or more C2-C9 hydrophobic moietiesare pendant to the core structure; wherein the one or more direct dyecompounds enter the hair shaft after the hair color composition isapplied to the hair; and wherein the hair color composition has a pH offrom about 6 to about 11; (b) rinsing the hair with water; wherein thepH of the hair after rinsing is from about 3.5 to about 6. Unlike azodyes in the yellow range that substitute pyridinium for imidazolium,these materials can be stable under conditions of use, particularly whenused in the presence of oxidants like hydrogen peroxide, which are foundin oxidation hair dye systems.

DETAILED DESCRIPTION OF THE INVENTION

While the specification concludes with claims which particularly pointout and distinctly claim the invention, it is believed the presentinvention will be better understood from the following description.

All percentages, parts and ratios are based upon the total weight of thecompositions of the present invention, unless otherwise specified. Allsuch weights as they pertain to listed ingredients are based on theactive level and, therefore, do not include solvents or by-products thatmay be included in commercially available materials, unless otherwisespecified. When more than one composition is used during a treatment, asin mixing of the components of a typical oxidative dye product, thetotal weight to be considered is the total weight of all thecompositions applied on the hair simultaneously (i.e. the weight found“on head”) unless otherwise specified. The term “weight percent” may bedenoted as “wt. %” herein.

As used herein, the term “hair” to be treated may be “living” i.e. on aliving body or may be “non-living” i.e. in a wig, hairpiece or otheraggregation of non-living keratinous fibers. Mammalian, particularlyhuman, hair is preferred. However, wool, fur, and other keratincontaining fibers are suitable substrates for the compositions accordingto the present invention.

As used herein, the term “pendant group” means a group of atoms attachedto the core structure or chromophore. As described herein, the pendantgroup itself is not colored although it may influence the color of thechromophore. The pendant group may be further classified as an anchoringgroup or a hydrophobic group. A hydrophobic group is typically a carbonchain. An anchoring group is a group attached to either a permanentcation or incipient cation, occasionally it is attached to both apermanent cation and one or more incipient cations.

As used herein, the term “chromophore” means the part of the direct dyecompound responsible for its color.

As used herein, the term “direct dye compound” means a dye used in aprocess in which dye molecules are attracted by physical forces at themolecular level to a textile or substrate such as the hair. As opposedto oxidative dyes, there is no chemical reaction required to form thechromophore. Additionally, there is no covalent bond formation betweenthe direct dye and the substrate as opposed to reactive dyes. The directdye compound does not undergo a chemical transformation before and afterthe dyeing process.

As used herein, the term “core structure” means the chromophoreincluding one or two permanent cations that are pendant to thechromophore or part of the chromophore. In an embodiment, thechromophore is charged. In an embodiment, the chromophore is not chargedas the permanent cation is pendant to the chromophore.

As used herein, the term “pendant” means when a functional group islinked to a core structure via covalent bond.

As used herein, the term “incipient cation” means a functional groupthat goes from neutral to positively charged due to protonation during achange in pH.

The hair colorant compositions of the present invention comprise one ormore washfast direct dyes, optionally, oxidative dyes as well.

With regards to the direct dye compounds described herein, numeroustautomeric compounds may be involved. Thus, for example,2-mercaptopyridine (I) may exist under known conditions in thepyridine-2-thione tautomer form (II).

It is to be understood that when this development refers to a particularstructure, all of the reasonable additional tautomeric structures areincluded. In the art, tautomeric structures are frequently representedby one single structure and the method described herein follows thisgeneral practice.

It is also understood that within the scope of this invention, E, Zisomers may be involved. Thus, for example, (E)-diphenyldiazene (III)converts under known conditions to (Z)-diphenyldiazene (IV), which isalso reversible.

It is to be understood that when this development refers to a particularstructure, all of the reasonable additional E, Z isomers are included.

I. Washfast Yellow Direct Dyes

Described herein is a method of dyeing the hair, the method comprising(a) applying to the hair a hair color composition comprising one or moredirect dye compounds; the one or more direct dye compounds eachcomprising (i) a yellow chromophore; (ii) one or two permanent cations,wherein the permanent cations are pendant to the chromophore or part ofthe chromophore, and wherein the chromophore and the permanent cationsform a core structure; and (iii) one to four incipient cations, whereinthe one to four incipient cations are pendant to the core structure, andwherein the incipient cations are neutral; and (iv) optionally one ormore C2-C9 hydrophobic moieties, alternatively C3-C9 hydrophobicmoieties, alternatively from C3-C6 hydrophobic moieties, wherein the oneor more C2-C9 hydrophobic moieties are pendant to the core structure;wherein the one or more direct dye compounds enter the hair shaft afterthe hair color composition is applied to the hair; and wherein the haircolor composition has a pH of from about 6 to about 11; (b) rinsing thehair with water; wherein the pH of the hair after rinsing is from about3.5 to about 6; and wherein the rinsing of the hair causes one or moreof the one to four incipient cations to change from neutral topositively charged inside of the hair shaft.

In an embodiment, the hair color composition has a pH of from about 6 toabout 11, alternatively from about 7 to about 11.

In an embodiment, the chromophore has a structure according to Formula Vor a tautomer or salt thereof:

wherein

-   -   (i) R_(1b), R_(1c) and R_(1f) are each independently hydrogen,        alkyl, halogen substituted alkyl, alkenyl, alkynyl, aryl,        hydroxyalkyl, aminoalkyl, alkyl group carrying a quaternary        ammonium cation, alkoxy, aryloxy, acyl, halogen, a heterocyclic        moiety, thioether, thiol with a linker group, alkylsulfonate,        alkylsulfate, carboxylalkyl, acrylamide or substituted        acrylamides with a linker group, vinylsulfone with a linker        group, sulfonyl ethyl sulfate with a linker group,        halo-s-triazines with a linker group, halopyrimidines with a        linker group, haloquinoxalines with a linker group, or are        attached to a polymer backbone through a linker;    -   (ii) R_(1a), R_(1d), and R_(1h) are each independently hydrogen,        alkyl, halogen substituted alkyl, alkenyl, alkynyl, aryl,        hydroxyalkyl, aminoalkyl, alkyl group carrying a quaternary        ammonium cation, a heterocyclic moiety, thiol with a linker        group, alkylsulfonate, alkylsulfate, carboxylalkyl, acrylamide        or substituted acrylamides with a linker group, vinylsulfone        with a linker group, sulfonyl ethyl sulfate with a linker group,        halo-s-triazines with a linker group, halopyrimidines with a        linker group, haloquinoxalines with a linker group, or are        attached to a polymer backbone through a linker;    -   (iii) R_(1e) and R_(1g) are each independently hydrogen, alkyl,        halogen substituted alkyl, alkenyl, alkynyl, aryl, hydroxyalkyl,        aminoalkyl, alkyl group carrying a quaternary ammonium cation, a        heterocyclic moiety, thiol with a linker group, alkylsulfonate,        alkylsulfate, carboxylalkyl, acrylamide or substituted        acrylamides with a linker group, vinylsulfone with a linker        group, sulfonyl ethyl sulfate with a linker group,        halo-s-triazines with a linker group, halopyrimidines with a        linker group, haloquinoxalines with a linker group, or are        attached to a polymer backbone through a linker, or part of a        cyclic structure and joined by substituted or unsubstituted        alkyl or heteroalkyl groups.

The one to four incipient cations, typically an amino group or groups,are attached to the chromophore in addition to the existing permanentcation(s) to overcome the problems encountered in previous attempts tomake cationic direct dyes more washfast. The chromophore would typicallycarry only one or two permanent positive charges such as quaternaryammonium salts, pyridinium, imidazolium, thiazolium, oxazolium,triazolium, pyrimidinium, triazinium, tetrazolium phenoxazinium,phenazinium or an analogous cation under basic conditions for typicalhair color applications. The amino group(s) would remain mostly neutralunder dyeing conditions (pH 10˜11) because the typical pK_(a) ofaliphatic amines falls between 9˜10.5. The dye would carry only one ortwo cationic charges under dyeing conditions, which provides the neededaffinity (Coulombic attraction) for optimized uptake without preventingpenetration due to relatively low charge density compared topolycationic dyes. However, once the coloring application is done andhair is rinsed, pH inside hair drops back to its natural pH, which isacidic, the amino group(s) attached to the chromophore would beprotonated to become an ammonium cation, which adds one or more bindingsites to the chromophore. The pH change functions as a convenient switchto turn on additional binding group(s) to make the chromophores morewashfast. Primary amines work the best when compared to secondary andtertiary amines for the following two reasons: 1. primary amines resistoxidation by hydrogen peroxide, while secondary and tertiary amines canbe oxidized and lose their anchoring capability when used together witha bleaching agent; 2. the protonated primary ammonium cation is thesmallest in size, which allows stronger interaction with anions on haircompared to secondary and tertiary amines with more steric hindrance.The following are examples of washfast dyes wherein one or moreincipient cations change from neutral to positively charged due a changeof pH. It is to be understood that the order and relative extent ofprotonation of the individual amines is a function of their specificpKa. Additionally, there is a variety of possible identities andarrangements of substituents, and the schemes below are for illustrativepurposes, and not exhaustive of the possibilities:

The linker groups, typically linear alkyl groups, would also function asmodulators for the overall hydrophobicity of the dye. One of the commondrawbacks of using exclusively cationic direct dyes for shading isoff-tone fading as different dyes would be washed off hair at differentrates, causing undesirable gradual color shift over time. Our technicalapproach minimizes off-tone fading by designing dyes of different colorswith identical charge patterns with similar overall hydrophobicity.Additionally, the fact that these inventive dyes are far more washfastthan typical cationic dyes also contributes to minimal color lost andon-tone fading.

The direct dye compounds may be substituted with one permanent cationiccharge, alternatively two permanent cationic charges. The direct dyecompounds may comprise one to three terminal amino groups andderivatives thereof, alternatively two terminal amino groups andderivatives thereof, and alternatively one terminal amino group andderivatives thereof, according to the following formula:

The chemical formulas of the direct dye compounds can be represented inthe following ways, but not limited to what is shown below:(L₂)_(y)-C*(-L₁-A)_(n)Z⁻  (VI)(A₁-L₁-)_(n)C*(-L₂-A₂)_(m)(L₃)_(y)Z⁻  (VII)(Q*-L₃-)_(x)C(-L₁-A₁)_(m)(-L₂-A₂)_(n)(L₄)_(y)(Z⁻)_(x) or Z^(x−)  (VIII)(L₃)_(y)-C(-L₁-Q*(-L₂-A)_(m))_(n)(Z⁻)_(n) or Z^(n−)  (IX)(L₂)_(y)-C*(-L₁-A₁-(L₃-A₂)_(m))_(n)Z⁻  (X)wherein

C is a chromophore;

Q* is an organic cation;

* stands for a permanent cationic charge, it can also be part of achromophore bearing a cationic charge;

L is a linker or hydrophobic chain and;

A is the anchoring group, the fastness enhancer. It is typically aprimary, secondary or tertiary amino group, preferably a primary amine.It is also a switch to allow the anchor to go between neutral andcharged states when the pH in the surrounding environment changes.

Z is a counter anion. It is typically a halide, sulfate, methylsulfate,hydrogen sulfate, phosphate, hydrogen phosphate, dihydrogen phosphate,nitrate, perchlorate, tetrafluoroborate, hexafluorophosphate, triflate,acetate, formate or hydroxide.

n=1˜4; m=1˜4; n+m<4; x=1˜2; y=0˜2.

The following are examples of the synthesis of various washfast directdye compounds as described herein:

Example 1

In example 1,(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-ium2,2,2-trifluoroacetate is prepared from 2-aminoimidazole and1-Methyl-1H-pyrazol-5-amine.

Synthesis of(E)-4-((1H-imidizol-2-yl)diazenyl)-1-methyl-1H-pyrazol-5-amine

Concentrated HCl (17.16 mL, 206 mmol) and 1H-imidazol-2-aminium sulfate(6.67 g, 25.1 mmol) were added to a 150 mL Erlenmeyer flask and cooledin ice/methanol bath to <0° C. Sodium nitrite (3.55 g, 51.48 mmol) isdissolved in ca. 20 mL of water and added dropwise to the solution abovekeeping the temperature below 5° C.

In a separate flask sodium carbonate (27.2 g, 257 mmol) is dissolved in200 mL of water. 1-Methyl-1H-pyrazol-5-amine (5 g, 51.48 mmol) is added.Upon cooling and stirring the solution became slushy. The2-aminoimidazole containing solution is added to the1-methyl-5-aminopyrzole solution, keeping the temperature below 5° C.Following complete addition the reaction mixture is kept cold andstirred for ca. 1 hour. Ethyl acetate (1 L) is added to the reactionmixture and the mixture is transferred to 2 L separatory funnel. Theethyl acetate is collected, and the aqueous phase is extracted twicemore with ethyl acetate (2×1 L). The extracts were combined andevaporated providing 5.0 g of a black semi-solid. The crude(E)-4-((1H-imidizol-2-yl)diazenyl)-1-methyl-1H-pyrazol-5-amine ispurified by column chromatography.

Synthesis of N-(4-bromopropyl)-2,2,2-trifluoroacetamide

To a mixture of 4-bromo-1-propylamine hydrobromide (8.76 g) and ethyltrifluoroacetate (6.82 g) in 100 mL of methanol at 0° C. is added 6.06 gof trimethylamine dropwise, carefully controlling the temperature. Thereaction solution is warmed to room temperature and stirred overnight.Solvent is evaporated under vacuum and the residue is dissolved inmethylene chloride. The solution is washed with water and 1M HCl andconcentrated. The crude N-(4-bromopropyl)-2,2,2-trifluoroacetamide isused in the next step without further purification.

Synthesis of(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl-1H-imidazol-3-iumbromide

(E)-4-((1H-imidizol-2-yl)diazenyl)-1-methyl-1H-pyrazol-5-amine (1.23 g,6.8 mmol) is dissolved in acetonitrile. Sodium bicarbonate (1.72 g, 20.5mmol) is added, followed by 3-bromopropyltrifluroroacetamide (4.8 g,20.5 mmol). The mixture is refluxed for 16 hours. Additional3-bromopropyltrifluoroacetamide (1.6 g, 6.8 mmol) is added and refluxcontinued for 24 hours. The hot reaction mixture is filtered thrucellulose filter paper and evaporated. The crude(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl-1H-imidazol-3-iumbromide is carried directly to the deprotection reaction.

Synthesis of (E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-ium 2,2,2-trifluoroacetate

Crude(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl-1H-imidazol-3-iumbromide is dissolved in 10 mL of 3M HCl and refluxed overnight. Thesolvent is evaporated and the crude product is chromatographed on areverse phase C-18 column providing 500 mg of pure(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-ium2,2,2-trifluoroacetate.

Example 2

In Example 2,(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidazol-3-iumbromide dihydrochloride is prepared from acrylonitrile and2-aminoimidazozle.

Synthesis of 3-hydrazinylpropanitrile

64-65% Hydrazine hydrate (1:1) (77 g, 0.992 mol) is dissolved in1-propanol (100 mL) and cooled in ice-methanol to −5° C. Acrylonitrile(55.65 g, 1.057 mol) is added dropwise keeping the internal temperaturebelow 0° C. The reaction is stirred at −5° C. for 30 minutes, andallowed to warm to room temperature for 1 hour. This material,3-hydrazinylpropanitrile, is used directly in the next reaction.

Synthesis of (E)-3-(2-hexylidenehydrazinyl)propanenitrile

1-hexanal (105 g, 1.05 mol) is added dropwise at room temperature to thefreshly prepared solution of 3-hydrazinylpropanitrile from the previousreaction, keeping the internal temperature below 30° C. The solution isstirred for 1 hour at room temperature followed by solvent evaporationproviding (E)-3-(2-hexylidenehydrazinyl)propanenitrile.

Synthesis of 1-hexyl-1H-pyrazol-5-amine

(E)-3-(2-hexylidenehydrazinyl)propanenitrile (72 g, 0.415 mol) is addedto a 500 mL round bottom flask along with 75 mL of 1-propanol. Sodiummethoxide, 25% (7.5 g, 34.7 mmol) is added and the mixture heated toreflux for 2-3 hours. The 1-propanol is evaporated and the residue isdistilled via short path distillation collecting 35 g of material at awide range of temperatures (84-140 C). The 35 g were chromatographed on2000 g of silica gel with very slow elution. The combined pure fractionsprovided 1-hexyl-1H-pyrazol-5-amine (29.5 g, 42%).

Synthesis of(E)-4-((1H-imidazol-2-yl)diazenyl)-1-hexyl-1H-pyrazol-5-amine

1H-Imidazol-2-aminium sulfate (4.15 g, 15.7 mmol) is dissolved inconcentrated HCl (10 mL, 119.56 mmol) and cooled in an ice-methanol bathto −5° C. Sodium nitrite (2.27 g, 32.88 mmol) is dissolved in minimumwater and added slowly to the 2-aminoimidazole keeping temperature below0° C. This is the diazonium salt and it is maintained at <0° C.

In a separate flask, 1-(hexyl)-5-aminopyrazole (5 g, 29.89 mmol) isdissolved in 5 mL of ethanol and water is added until just before thecloud point is reached. Sodium carbonate (15.8 g, 149.45 mmol) is addedto this solution. The cold diazonium salt is added to the slushysolution of 1-hexyl-1H-pyrazol-5-amine resulting in a black mixture. Theinternal temperature drops slightly during addition due to the colderdiazonium salt thus the diazonium salt can be added at a moderate rate.Following complete diazo addition the mixture is stirred at 0° C. for 1hour and then warmed to room temperature and stirred for 2 hours. Thereaction mixture is diluted with water. The black aqueous phase istransferred to a separatory funnel and extracted with ethyl acetate(2×500 mL). The resulting ethyl acetate extracts are combined andevaporated providing 6 g of material. This material is chromatographedon silica gel. The combined pure fractions provide(E)-4-((1H-imidazol-2-yl)diazenyl)-1-hexyl-1H-pyrazol-5-amine (4 g,51%).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide

(E)-4-((1H-imidazol-2-yl)diazenyl)-1-hexyl-1H-pyrazol-5-amine (14.43 g,55.22 mmol) is dissolved in 300 mL of acetonitrile. Sodium bicarbonate(10.20 g, 121.5 mmol) and 3-bromopropyl trifluoroacetamide (28.43 g,121.5 mmol) were added and the reaction heated to reflux. The reactionis refluxed further for several days along with additional 3-bromopropyltrifluoroacetamide (12 g) and 300 mL of additional acetonitrile. Themixture is evaporated providing 54 g of material. This ischromatographed on silica gel columns yielding 19.5 g (54%) of pure(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide.

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride

(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide (19.5 g, 30.1 mmol) is suspended in 80 mL (0.9 mol) ofconcentrated HCl and refluxed for 2 hours. The hydrochloric acid isevaporated and the product triturated with ethyl acetate (250 mL). Thissuspension is filtered under inert atmosphere providing(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride (14.7 g, 92% yield).

Example 3

In Example 3,(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide dichloride is prepared from2-(5-amino-1H-pyrazol-1-yl)ethan-1-ol and 1H-imidazol-2-amine.

Synthesis of(E)-2-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)ethan-1-ol

2-Aminoimidazole (5.0 g, 37.8 mmol) is dissolved in concentrated HCl(12.6 mL, 151 mmol) and cooled in an ice-methanol bath to −5° C. Sodiumnitrite (2.61 g, 37.8 mmol) is dissolved in the minimum of water (<4 mL)and added slowly to the 2-aminoimidazole keeping temperature below 0° C.This is the diazonium salt and it is maintained at <0° C.

In a separate flask, 2-(5-amino-1H-pyrazol-1-yl)ethan-1-ol (5 g, 29.89mmol) is dissolved in 5 mL of ethanol and water is added until justbefore the cloud point is reached. Sodium carbonate (19.96 g, 189.0mmol) is added. The mixture is cooled in an ice-water bath to ca. 5° C.resulting in a solution having a slushy consistency. The cold diazoniumsalt is added to the slushy solution of the2-(5-amino-1H-pyrazol-1-yl)ethan-1-ol resulting in a black mixture.Following complete diazo addition the mixture is stirred at 0° C. for 1hour and allowed to warm to room temperature and then stirred for 2hours. The reaction mixture is diluted with water. The black aqueousphase is extracted with cold ethyl acetate and then hot ethyl acetate(500 mL each) providing 3 g of material. The aqueous phase from theextraction is evaporated and triturated with ethyl acetate, whichgenerated an additional 3 g of material. The combined 6 g ischromatographed on silica gel to provide pure(E)-2-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)ethan-1-ol(1.26 g, 15%).

Synthesis of(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido) propyl)-1H-imidazol-3-ium bromide

(E)-2-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)ethan-1-ol(1.3 g, 5.88 mmol) is dissolved in 300 mL of acetonitrile. Sodiumbicarbonate (0.99 g, 11.76 mmol) andN-(3-bromopropyl)-2,2,2-trifluoroacetamide (3.03 g, 12.94 mmol) wereadded and the reaction heated to reflux. AdditionalN-(3-bromopropyl)-2,2,2-trifluoroacetamide (1.0 g, 800 mg, and 1.0 g) isadded at twenty-four hour intervals and reflux is continued for 24hours. After 8 days the hot reaction mixture is filtered and thefiltrate evaporated. The residue is chromatographed on silica gel toprovide pure(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-ium bromide (1.2 g, 35% yield)

Synthesis of(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-ium bromide dichloride

(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-ium bromide (1.2 g, 1.97 mmol) is suspended in 8mL (24 mol) of 3M HCl and refluxed for 2 hours. The hydrochloric acid isevaporated and the product triturated with ethyl acetate (250 mL). Thissuspension is subsequently filtered under inert atmosphere, providing(E)-2-((5-amino-1-(2-hydroxyethyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide dichloride (0.90 g, 94% yield).

Example 4

In example 4,(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-methyl-1H-imidazol-3-iumbromide chloride is prepared from 2-aminoimidazole and1-hexyl-1H-pyrazol-5-amine.

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-methyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

(E)-4-((1H-imidazol-2-yl)diazenyl)-1-hexyl-1H-pyrazol-5-amine (3.0 g,11.48 mmol) is dissolved in 200 mL of acetonitrile. Sodium bicarbonate(2.89 g, 34.44 mmol) and iodomethane (4.88 g, 34.44 mmol) were added andthe reaction heated to reflux for 3.25 hours. The hot reaction mixtureis filtered to remove sodium bicarbonate and the solvent evaporated. Thecrude solid is chromatographed on silica gel to provide(E)-1-hexyl-4-((1-methyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-5-amine(0.90 g, 28% yield).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-methyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

(E)-1-hexyl-4-((1-methyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-5-amine(1.0 g, 3.67 mmol) is dissolved in 100 mL of acetonitrile. Sodiumbicarbonate (0.34 g, 4.03 mmol) andN-(3-bromopropyl)-2,2,2-trifluoroacetamide (1.89 g, 8.06 mmol) wereadded and the reaction heated to reflux for 20 hours. The hot reactionmixture is filtered and the solvent evaporated. The crude product ischromatographed on silica gel to provide(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-methyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (1.01 g, 65% yield).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-methyl-1H-imidazol-3-iumbromide chloride

(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-methyl-1-(3-(2,2,2-trifluoroacetamido)-propyl)-1H-imidazol-3-iumbromide (1.0 g, mmol) is suspended in 8 mL (24 mmol) of 3M HCl andrefluxed for 2 hours. The hydrochloric acid is evaporated and theproduct triturated with ethyl acetate (250 mL). This suspension isfiltered under inert atmosphere to provide(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-methyl-1H-imidazol-3-iumbromide chloride (0.710 g, 90% yield).

Example 5

In Example 5,(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-propyl-1H-imidazol-3-iumbromide chloride is prepared from 1-hexyl-1H-pyrazol-5-amine and1H-imidazol-2-amine.

Synthesis of(E)-N-(3-(2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1H-imidazol-1-yl)propyl)-2,2,2-trifluoroacetamide

(E)-4-((1H-imidazol-2-yl)diazenyl)-1-hexyl-1H-pyrazol-5-amine (3.0 g,11.48 mmol) is dissolved in 200 mL of acetonitrile. Sodium bicarbonate(2.89 g, 34.44 mmol) and N-(3-bromopropyl)-2,2,2-trifluoroacetamide(8.06 g, 34.44 mmol) were added and the reaction heated to reflux for 5hours. The temperature is reduced to 60° C. and heated overnight. Thetemperature is then returned to reflux for 8 hour. The hot solution isfiltered thru cellulose filter paper to remove sodium bicarbonate andevaporated. The crude product is chromatographed on silica gel toprovide(E)-N-(3-(2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1H-imidazol-1-yl)propyl)-2,2,2-trifluoroacetamide(1.35 g, 28% yield).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-propyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

(E)-N-(3-(2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1H-imidazol-1-yl)propyl)-2,2,2-trifluoroacetamide(0.70 g, 1.69 mmol) is dissolved in 25 mL of acetonitrile. Sodiumbicarbonate (200 mg, 2.38 mmol) and 1-bromopropane (1.0 g, 8.13 mmol)were added, followed by heating to reflux for 16 hours. The hot reactionmixture is filtered through cellulose paper to remove sodiumbicarbonate. The crude product is chromatographed on silica gelproviding pure(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-propyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (0.37 g, 48% yield).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-propyl-1H-imidazol-3-iumbromide chloride

(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-propyl-1-(3-(2,2,2-trifluoroacetamido)-propyl)-1H-imidazol-3-iumbromide (0.37 g, 0.688 mmol) is suspended in 3 mL (6.88 mmol) of 3M HCland refluxed for 2 hours. The hydrochloric acid is evaporated and theproduct is triturated with ethyl acetate (250 mL). This suspension isfiltered under inert atmosphere providing(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-propyl-1H-imidazol-3-iumbromide chloride (0.30 g, 90% yield).

Example 6

(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-hexyl-1H-imidazol-3-iumbromide chloride is prepared from 1-hexyl-1H-pyrazol-5-amine and1H-imidazol-2-amine.

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-hexyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

(E)-N-(3-(2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1H-imidazol-1-yl)propyl)-2,2,2-trifluoroacetamide(0.650 g, 1.57 mmol) is dissolved in 25 mL of acetonitrile. Sodiumbicarbonate (200 mg, 2.38 mmol) and 1-bromohexane (1.035 g, 6.27 mmol)were added followed by heating to reflux for 16 hours. The hot reactionmixture is filtered through cellulose paper to remove sodiumbicarbonate. The crude product is chromatographed on silica gel toprovide pure(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-hexyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (0.30 g, 38% yield).

Synthesis of(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-hexyl-1H-imidazol-3-iumbromide chloride

(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-3-hexyl-1-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (0.30 g, 0.518 mmol) is suspended in 3 mL (9 mmol) of 3M HCl andrefluxed for 2 hours. The hydrochloric acid is evaporated and theproduct triturated with ethyl acetate (250 mL). This suspension issubsequently filtered under inert atmosphere providing(E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1-(3-ammoniopropyl)-3-hexyl-1H-imidazol-3-iumbromide chloride (0.240 g, 90% yield).

Example 7

In Example 7, is prepared from t-butyl (3-hydroxypropyl)carbamate and2-aminoimidazole.

Synthesis of t-butyl (3-oxopropyl)carbamate

t-Butyl (3-hydroxypropyl)carbamate (15.3 g, 87.3 mmol) is dissolved indichloromethane (200 mL) and 50 mL of water were added. Sodium bromide(9.43 g, 91.68 mmol) and sodium bicarbonate (8.07 g, 96.05 mmol) wereadded and the mixture cooled in ice/water bath to ca. 5° C. TEMPO (100mg, 0.873 mmol) is added followed by the dropwise addition of sodiumhypochlorite (102 mL, 113.5 mmol) at a moderate rate. The solution turnsreddish-brown and this color fades to colorless as the reactionproceeds. Subsequently, additional (required) sodium hypochlorite isadded in 10 mL portions until conversion is complete. Thedichloromethane phase is collected and the aqueous phase is extractedone additional time with dichloromethane (250 mL) and the combinedextracts washed with 10% sodium thiosulfate (100 mL). Thedichloromethane portion is dried (MgSO₄), filtered and evaporated toafford t-butyl (3-oxopropyl)carbamate (12.5 g, 72 mmol) as a colorlessoil.

Synthesis of tert-butyl (3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate

t-Butyl (3-oxopropyl)carbamate (2.32 g, 13.4 mmol) is dissolved in1-propanol (20 mL). Cyanopropylhydrazine (1.14 g, 13.4 mmol) isdissolved in 10 mL of 1-propanol and added at room temperature. Theinternal temperature rises slightly to ca. 27° C. Stirring is continuedovernight. 25% Sodium methoxide (1.0 g, 4.6 mmol) is added and thereaction heated to reflux for 2 hours. The mixture is evaporated,re-dissolved in dichloromethane and washed with water and saturatedNaHCO₃ and the dichloromethane phase evaporated. The resulting oil ischromatographed on silica gel to afford t-butyl(3-(5-amino-1H-pyrazol-1-yl)propyl)-carbamate (0.750 g, 3.12 mmol).

Synthesis of (E)-N′-(1H-imidazol-2-yl)-N,N-dimethylformimidamide

2-Aminoimidazole (13.3 g, 100 mmol) is dissolved in water. Sodiumcarbonate (15.93 g, 151 mmol) is added and the mixture stirredvigorously at room temperature for 1 hour, after which the water isevaporated. The resulting solid is suspended in ethanol, stirred for 1hour and filtered through a pad of Celite. The filtrate is evaporatedand then dissolved in dimethylformamide dimethylacetal (50 mL) andstirred overnight with ethyl acetate (150 mL). The suspended solids werecollected by filtration affording(E)-N′-(1H-imidazol-2-yl)-N,N-dimethylformimidamide (9.64 g, 69.7 mmol)in sufficient purity to use in the subsequent alkylation reaction.

Synthesis of (E)-N′-(1-hexyl-1H-imidazol-2-yl)-N,N-dimethylformimidamide

(E)-N′-(1H-imidazol-2-yl)-N,N-dimethylformimidamide (6.0 g, 43.43 mmol)is dissolved in dimethylformamide (100 mL). Potassium t-butoxide (9.75g, 86.85 mmol) is added, followed by 1-bromohexane (10.75 g, 65.14 mmol)and the mixture stirred at 40° C. overnight. The reaction mixture isthen quenched with water (50 mL), followed by acidification withconcentrated HCl and extraction with dichloromethane. The combineddichloromethane extracts were dried (MgSO₄), filtered, and evaporated toafford a wet solid. The wet solid is heated to remove dimethylformamideaffording (E)-N′-(1-hexyl-1H-imidazol-2-yl)-N,N-dimethylformimidamide(10.0 g, quantitative yield).

Synthesis of 1-hexyl-1H-imidazol-2-aminium chloride

(E)-N′-(1-hexyl-1H-imidazol-2-yl)-N,N-dimethylformimidamide (9.66 g,43.5 mmol) is suspended in 6N HCl (50 mL) and refluxed for 3 hours. Thesolvent is evaporated and the dry solid triturated with ethyl ether. Thesuspended solids were collected via filtration affording1-hexyl-1H-imidazol-2-aminium chloride (8.3 g, 40.7 mmol) as anoff-white solid.

Synthesis of t-butyl(E)-(3-(5-amino-4-((1-hexyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate

1-Hexyl-1H-imidazol-2-aminium chloride (1.58 g, 7.61 mmol) is dissolvedin water (20 mL). Concentrated HCl (3.09 g, 30.44 mmol) is added and themixture cooled in ice/methanol bath to −5° C. Sodium nitrite (0.57 g,9.51 mmol) is dissolved in a minimum amount of water and added dropwiseto the above mixture keeping the temperature below 0° C. The reactionmixture is allowed to stir for 30-60 minutes at <0° C. without allowingit to freeze. t-Butyl (3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate (1.55g, 6.45 mmol) is dissolved in methanol (50 mL) and water (200 mL).Sodium carbonate (4.09 g, 38.04 mmol) is added and the solution cooledin ice/water bath. The above diazonium salt is added dropwise to thissolution keeping the temperature at 5° C. The reaction mixture isallowed to warm to room temperature over 1 hour then extracted with2×500 mL of ethyl acetate. The combined ethyl acetate extracts wereconcentrated and the residue chromatographed on silica gel providingpure t-butyl(E)-(3-(5-amino-4-((1-hexyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate(0.90 g, 2.15 mmol).

Synthesis of(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-hexyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

t-Butyl(E)-(3-(5-amino-4-((1-hexyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate(0.85 g, 2.03 mmol) is suspended in acetonitrile (50 mL).N-(3-bromopropyl)-2,2,2-trifluoroacetamide (0.62 g, 2.63 mmol) added,followed by sodium bicarbonate (0.201 g, 2.40 mmol) and the mixturerefluxed overnight. The crude product is chromatographed on silica gelto afford pure(E)-2-((5-amino-1-(3-((t-butoxycarbonyl)amino)-propyl)-1H-pyrazol-4-yl)diazenyl)-1-hexyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (1.0 g, 1.53 mmol).

Synthesis of(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-hexyl-1H-imidazol-3-iumbromide dichloride

(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-hexyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (1.0 g, 1.53 mmol) is dissolved in 3M HCl (5 mL) and refluxedfor 3 hours. The solvent is evaporated and the orange solid isre-dissolved in methanol and added to cold (−5° C.) ethyl acetate. Theresulting precipitate is collected providing pure(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-hexyl-1H-imidazol-3-iumbromide dichloride (0.79 g, 1.50 mmol).

Example 8

In Example 8,(E)-3-(3-aminopropyl)-1-hexyl-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is prepared by cyclization of(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-hexyl-1H-imidazol-3-iumbromide dichloride in aqueous ammonium hydroxide.

(E)-3-(3-aminopropyl)-1-hexyl-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide

(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-hexyl-1H-imidazol-3-iumbromide dichloride is dissolved in aqueous ammonium hydroxide (2.25 g of28% ammonium hydroxide and 97.75 g of water). After standing overnight,conversion to(E)-3-(3-aminopropyl)-1-hexyl-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is quantitative.

Example 9

In Example 9,(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride is prepared from t-butyl(3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate and 2-aminoimidazole.

Synthesis of t-butyl(E)-(3-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)propyl)carbamate

2-Aminoimidazole hemisulfate (10 g, 37.95 mmol) is dissolved in water(50 mL), concentrated HCl (25 g, 253 mmol) and the mixture cooled inice/methanol bath to −5° C. Sodium nitrite (5.24 g, 76 mmol) isdissolved in a minimum amount of water and added dropwise, keeping thetemperature below 0° C. The reaction mixture is allowed to stir for30-60 minutes at <0° C. without allowing it to freeze. The t-butyl(3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate (7.6 g, 31.63 mmol) isdissolved in methanol (50 mL) and water (200 mL). Sodium carbonate (33.4g, 317 mmol) is added and the solution cooled in ice/water bath. Thediazonium salt is added dropwise to this solution keeping thetemperature around 5° C. The reaction mixture is allowed to warm to roomtemperature over 1 hour then extracted with 2×1 L of ethyl acetate. Theethyl acetate is evaporated and the residue chromatographed on silicagel, providing pure t-butyl(E)-(3-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)propyl)carbamate(2.34 g, 5.6 mmol).

Synthesis of(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-ium bromide

t-Butyl(E)-(3-(4-((1H-imidazol-2-yl)diazenyl)-5-amino-1H-pyrazol-1-yl)propyl)carbamate(0.40 g, 1.2 mmol) is suspended in acetonitrile (50 mL) and refluxed.N-(3-bromopropyl)-2,2,2-trifluoroacetamide (0.62 g, 2.63 mmol) andsodium bicarbonate (0.201 g, 2.40 mmol) were added and the reactionstirred at reflux overnight. The reaction mixture is filtered hot toremove sodium bicarbonate and the filtrate evaporated. The crude productis chromatographed on silica gel to afford pure(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-hexyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (0.70 g, 0.97 mmol).

Synthesis of(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride

(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (0.70 g, 0.97 mmol) is dissolved in 3M HCl (5 mL) and refluxedfor 3 hours. The solvent is evaporated, the solid re-dissolved inmethanol and added to a cold (−5° C.) solution of ethyl acetate. Theresulting precipitate is collected via filtration providing pure(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride (0.52 g, 0.968 mmol).

Example 10

In Example 10,(E)-1,3-bis(3-aminopropyl)-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is prepared by cyclization(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride.

(E)-1,3-bis(3-aminopropyl)-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide

(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride is dissolved in aqueous ammonium hydroxide (2.25 gof 28% ammonium hydroxide and 97.75 g of water). After standingovernight, conversion to(E)-1,3-bis(3-aminopropyl)-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is quantitative.

Example 11

In Example 11,(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-propyl-1H-imidazol-3-iumbromide dichloride is prepared from(E)-N′-(1H-imidazol-2-yl)-N,N-dimethylformimidamide and t-butyl(3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate

Synthesis of(E)-N,N-dimethyl-N′-(1-propyl-1H-imidazol-2-yl)formimidamide

(E)-N′-(1H-imidazol-2-yl)-N,N-dimethylformimidamide (4.82 g, 34.63 mmol)is dissolved in dimethylformamide (100 mL). Potassium t-butoxide (8.55g, 76.2 mmol) is added followed by 1-bromopropane (6.39 g, 51.95 mmol)and the mixture stirred at 40° C. overnight. The reaction mixture isthen quenched with water (50 mL), followed by acidification withconcentrated HCl and extraction with dichloromethane. The combineddichloromethane extracts were washed with water (3×100 mL) dried(MgSO₄), filtered, and evaporated affording very pure(E)-N′-(1-propyl-1H-imidazol-2-yl)-N,N-dimethylformimidamide (6.0 g,96%).

Synthesis of l-propyl-1H-imidazol-2-aminium chloride

(E)-N′-(1-propyl-1H-imidazol-2-yl)-N,N-dimethylformimidamide (6.24 g,34.6 mmol) is suspended in 6N HCl (50 mL) and refluxed for 3 hours.After most of the water is removed the solution is re-dissolved in 1NNaOH and this solution evaporated to remove the possible dimethylamineimpurity. Following complete evaporations the crude product is dissolvedin 1N HCl and the solvent is evaporated. The dry solid is trituratedwith ethyl ether. The suspended solids were collected via filtrationaffording 1-propyl-1H-imidazol-2-aminium chloride (5.3 g, 40.7 mmol) asa crude, off-white solid.

Synthesis of tert-butyl(E)-(3-(5-amino-4-((1-hexyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate

1-Propyl-1H-imidazol-2-aminium chloride (1.0 g, 6.2 mmol) is dissolvedin water (20 mL), concentrated HCl (2.69 g, 27.22 mmol) is added and themixture cooled in ice/methanol bath to −5° C. Sodium nitrite (0.57 g,6.81 mmol) is dissolved in a minimum amount of water and added dropwiseto the above mixture keeping the temperature below 0° C. The reactionmixture is allowed to stir for 30-60 minutes at <0° C. without allowingit to freeze. The t-butyl (3-(5-amino-1H-pyrazol-1-yl)propyl)carbamate(1.635 g, 6.81 mmol) is dissolved the minimum amount of methanol (5 mL)and water added to the cloud point. This solution is added to the abovediazonium salt keeping the temperature around 5° C. After 15-30 minutesthere is a heavy black precipitate in the reaction. While stirring themixture, 50% NaOH is added dropwise until the mixture is ca. pH 10.0.The resulting mixture is extracted several times with 200 mL ethylacetate. The combined ethyl acetate extracts were evaporated and theresidue chromatographed on silica gel providing pure t-butyl(E)-(3-(5-amino-4-((1-propyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate(1.05 g, 2.8 mmol).

Synthesis of(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-propyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide

t-Butyl(E)-(3-(5-amino-4-((l-propyl-1H-imidazol-2-yl)diazenyl)-1H-pyrazol-1-yl)propyl)carbamate(1.05 g, 2.8 mmol) is suspended in acetonitrile (50 mL) andN-(3-bromopropyl)-2,2,2-trifluoroacetamide (1.44 g, 6.14 mmol) is addedand the mixture refluxed overnight. AdditionalN-(3-bromopropyl)-2,2,2-trifluoroacetamide (0.700 g, 2.99 mmol) is addedand the mixture is refluxed overnight. The solvent is evaporated and thecrude product is chromatographed on silica gel to afford pure(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-propyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (1.0 g, 1.53 mmol).

Synthesis of(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-propyl-1H-imidazol-3-iumbromide dichloride

(E)-2-((5-amino-1-(3-((tert-butoxycarbonyl)amino)propyl)-1H-pyrazol-4-yl)diazenyl)-1-propyl-3-(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidazol-3-iumbromide (1.0 g, 1.53 mmol) is dissolved in 3M HCl (5 mL) and refluxedfor 3 hours. The solvent is evaporated and the orange solid isre-dissolved in methanol and added to a cold (−5° C.) solution of ethylacetate. The resulting precipitate is collected via filtration providingpure(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-3-(3-ammoniopropyl)-1-propyl-1H-imidazol-3-iumbromide dichloride (0.70 g, 1.43 mmol).

Example 12

In Example 12,(E)-3-(3-aminopropyl)-1-propyl-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is prepared by cyclization(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride.

(E)-3-(3-aminopropyl)-1-propyl-2-((4, 5, 6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide

(E)-2-((5-amino-1-(3-ammoniopropyl)-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide trichloride is dissolved in aqueous ammonium hydroxide (2.25 gof 28% ammonium hydroxide and 97.75 g of water). After standingovernight, conversion to(E)-3-(3-aminopropyl)-1-propyl-2-((4,5,6,7-tetrahydropyrazolo[1,5-a]pyrimidin-3-yl)diazenyl)-1H-imidazol-3-iumbromide is quantitative.

Example 13

In Example 13,(E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-ammoniopropyl)-1H-imidazol-3-iumbromide dichloride is prepared from acrylonitrile and 2-aminoimidazole.

Synthesis of 3-hydrazinylpropanitrile

64-65% Hydrazine hydrate (1:1) (11.2 g, 0.224 mol) is dissolved in1-propanol (200 mL) and cooled in ice-methanol to −5° C. Acrylonitrile(12.47 g, 0.235 mol) is added dropwise keeping the internal temperaturebelow 0° C. The reaction is stirred at −5° C. for 30 minutes and thenallowed to warm to room temperature and stirred for 1 hour. Thismaterial, 3-hydrazinylpropanitrile, is used directly in the nextreaction.

Synthesis of (E)-3-(2-propylidenehydrazinyl)propanenitrile

1-Propionaldehyde (6.8 g, 117 mmol) is added dropwise at roomtemperature to a portion of the freshly prepared3-hydrazinylpropanitrile solution (theoretical 6.125 g, 72 mmol) above,keeping the internal temperature below 30° C. The solution is stirredfor 1 hour at room temperature followed by solvent evaporation providing(E)-3-(2-propylidenehydrazinyl)-propanenitrile.

Synthesis of 1-propyl-1H-pyrazol-5-amine

(E)-3-(2-propylidenehydrazinyl)propanenitrile (9.0 g, 71.88 mmol) isadded to a 250 mL round bottom flask along with 100 mL 1-propanol.Sodium methoxide, 25% (1.55 g, 7.18 mmol) is added and the mixtureheated to reflux for 3 hours after which additional sodium methoxide(1.5 g) is added and reflux continued over the weekend. The 1-propanolis evaporated and the residue chromatographed on silica gel to afford1-propyl-1H-pyrazol-5-amine (4.0 g, 32 mmol).

Synthesis of(E)-4-((1H-imidazol-2-yl)diazenyl)-1-propyl-1H-pyrazol-5-amine

2-Aminoimidazole (5.99 g, 22.7 mmol) is dissolved in water (50 mL)followed by the addition of concentrated hydrochloric acid (8.94 g,90.67 mmol) and acetic acid (2.72 g, 45.33 mmol). This mixture is cooledin an ice-methanol bath to −5° C. Sodium nitrite (3.13 g, 45.33 mmol) isdissolved in a minimum amount of water (<4 mL) and added slowly to the2-amino-imidazole keeping temperature below 0° C. This diazonium salt ismaintained at <0° C.

In a separate flask, 1-propyl-1H-pyrazol-5-amine (4 g, 41.21 mmol) isdissolved in a minimum amount of ethanol and water is added to the cloudpoint. This solution is added to the diazonium salt above keepingtemperature below 5° C. After 15-30 minutes at <5° C. the resultingblack heterogeneous solution is made basic via the addition of 50% NaOH.NaOH is added while stirring. The resulting solution is extractedseveral times with ethyl acetate. The ethyl acetate is evaporated. Thecrude product is chromatographed on silica gel affording pure(E)-4-((1H-imidazol-2-yl)diazenyl)-1-propyl-1H-pyrazol-5-amine (3.1 g,14.1 mmol).

Synthesis of(E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide

(E)-4-((1H-imidazol-2-yl)diazenyl)-1-propyl-1H-pyrazol-5-amine (2.0 g,9.12 mmol) is dissolved in 100 mL of acetonitrile. Sodium bicarbonate(1.68 g, 27.4 mmol) and 3-bromopropyl trifluoroacetamide (6.4 g, 27.4mmol) were added and the reaction heated to reflux overnight. Thereaction is filtered hot to remove sodium bicarbonate and the solventevaporated. The resulting residue is chromatographed on silica gelaffording(E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide (4.1 g, 6.77 mmol).

Synthesis of (E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-ium bromide dihydrochloride

(E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)-propyl)-1H-imidizol-3-iumbromide (2.0 g, 30.1 mmol) is suspended in 25 mL (0.9 mol) ofconcentrated HCl and refluxed for 2 hours. The hydrochloric acid isevaporated and the product dissolved in a minimum of methanol followedby addition to cold (−5° C.) ethyl acetate (150 mL). This suspension issubsequently filtered under inert atmosphere to afford pure(E)-2-((5-amino-1-propyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride (1.38 g, 2.83 mmol).

Example 14

In Example 14,(E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride is prepared from 2-aminoimidazole andacrylonitrile.

Synthesis of 3-hydrazinylpropanitrile

64-65% Hydrazine hydrate (1:1) (11.2 g, 0.224 mol) is dissolved in1-propanol (200 mL) and cooled in ice-methanol to −5° C. Acrylonitrile(12.47 g, 0.235 mol) is added dropwise keeping the internal temperaturebelow 0° C. The reaction is stirred at −5° C. for 30 minutes, and thenwarmed to room temperature and stirred for 1 hour. This material,3-hydrazinylpropanitrile, is used directly in the next reaction.

Synthesis of (E)-3-(2-propylidenehydrazinyl)propanenitrile

1-Butanal (8.475 g, 117 mmol) is added dropwise at room temperature tothe freshly prepared solution of 3-hydrazinylpropanitrile (6.125 g, 72mmol) from the previous reaction, keeping the internal temperature below30° C. The solution is stirred for 1 hour at room temperature followedby solvent evaporation providing(E)-3-(2-butylidenehydrazinyl)propanenitrile.

Synthesis of 1-butyl-1H-pyrazol-5-amine

(E)-3-(2-butylidenehydrazinyl)propanenitrile (10 g, 72 mmol) is added toa 250 mL round bottom flask along with 100 mL 1-propanol. Sodiummethoxide, 25% (5.0 g, 23 mmol) is added and the mixture heated toreflux for 48 hours after which the solvent is evaporated andchromatographed on silica gel afford pure 1-butyl-1H-pyrazol-5-amine(4.3 g, 31 mmol).

Synthesis of(E)-4-((1H-imidazol-2-yl)diazenyl)-1-butyl-1H-pyrazol-5-amine

2-Aminoimidazole (1.14 g, 4.35 mmol) is dissolved in water (20 mL)followed by the addition of concentrated hydrochloric acid (3.12 g, 31.6mmol) and acetic acid (0.522 g, 8.69 mmol). This mixture is cooled in anice-methanol bath to −5° C. Sodium nitrite (0.60 g, 8.69 mmol) isdissolved in a minimum amount of water (<2 mL) and added slowly to the2-aminoimidazole containing solution, keeping temperature below 0° C.The diazonium salt and it is maintained at <0° C.

In a separate flask, 1-butyl-1H-pyrazol-5-amine (1.1 g, 7.9 mmol) isdissolved in a minimum amount of ethanol, and water is added to thecloud point. This solution is added to the diazonium salt above, keepingtemperature below 5° C. After 15-30 minutes at <5° C. the resultingblack heterogeneous solution is made basic via the addition of 50% NaOH,with stirring. The solution is extracted several times with ethylacetate. The ethyl acetate extracts are combined and evaporated. Thecrude product is chromatographed on silica gel affording pure(E)-4-((1H-imidazol-2-yl)diazenyl)-1-butyl-1H-pyrazol-5-amine (0.750 g,3.44 mmol).

Synthesis of (E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-ium bromide

(E)-4-((1H-imidazol-2-yl)diazenyl)-1-butyl-1H-pyrazol-5-amine (0.750 g,3.44 mmol) is dissolved in 30 mL of acetonitrile. Sodium bicarbonate(0.54 g, 6.43 mmol) and 3-bromopropyl trifluoroacetamide (2.26 g, 9.65mmol) were added and the reaction is heated to reflux overnight. Thereaction is filtered hot to remove sodium bicarbonate and the solvent isevaporated. The resulting residue is chromatographed on silica gelaffording(E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide (0.88 g, 1.45 mmol).

Synthesis of(E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride

(E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-(2,2,2-trifluoroacetamido)propyl)-1H-imidizol-3-iumbromide (0.88 g, 1.45 mmol) is suspended in 10 mL of concentrated HCland refluxed for 2 hours. The hydrochloric acid is evaporated and theproduct dissolved in a minimum of methanol followed by addition to cold(−5° C.) ethyl acetate (100 mL). This suspension is filtered under inertatmosphere and affords pure(E)-2-((5-amino-1-butyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidizol-3-iumbromide dihydrochloride (0.67 g, 1.37 mmol).

Example 15

In example 15,(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl)-1,3-dimethyl-1H-imidazol-3-iummethyl sulfate is prepared from 2-aminoimidazole and1-Methyl-1H-pyrazol-5-amine.

Synthesis of(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl)-1,3-dimethyl-1H-imidazol-3-ium

A solution of 191 mg of crude(E)-4-((1H-imidazol-2-yl)diazenyl)-1-methyl-1H-pyrazol-5-amine, 504 mgof NaHCO₃, and 568 mg of dimethyl sulfate in 10 mL of acetonitrile isheated under reflux for 4 hours. The reaction mixture is filtered hot,and the filtrate is evaporated to dryness. The residue is dissolved in aminimum amount of methanol, the solution is poured into cold ethylacetate, and the precipitate is collected, yielding 66 mg of(E)-2-((5-amino-1-methyl-1H-pyrazol-4-yl)diazenyl)-1,3-dimethyl-1H-imidazol-3-iummethyl sulfate as a yellowish solid.

Exemplary Formulations % by weight Composition A Direct Dye¹ 0.01-2.5Ammonium Hydroxide (aq. 28% active) 4.50 Water q.s. to 100 Composition BDirect Dye¹ 0.01-2.5 Ammonium carbonate 10.00 Water q.s. to 100Composition C Direct Dye¹ 0.01-2.5 FlexiThix ™³ 5.00 Phenoxyethanol 0.30Sodium Benzoate 0.30 Disodium EDTA 0.10 Ammonium Hydroxide (aq. 28%active) 4.00 Water q.s. to 100 Composition D Direct Dye¹ 0.01-2.5Aculyn ™ 46⁴ 15.80 Phenoxyethanol 0.30 Sodium Benzoate 0.30 DisodiumEDTA 0.10 Ammonium Hydroxide (aq. 28% active) 4.00 Water q.s. to 100Composition E Direct Dye¹ 0.01-2.5 Plantaren ® 2000 N UP² 20.00Phenoxyethanol 0.30 Sodium Benzoate 0.30 Disodium EDTA 0.10 AmmoniumHydroxide (aq. 28% active) 4.00 Water q.s. to 100 Composition F DirectDye¹ 0.01-2.5 Non-anionic foaming agent 5.00 Phenoxyethanol 0.30 SodiumBenzoate 0.30 Disodium EDTA 0.10 Ammonium Hydroxide (aq. 28% active)4.00 Water q.s. to 100 % by weight ¹The direct dye may be any one of thedirect dyes described herein ²Chemical makeup supplied by BASF ³PVPpolymer supplied by Ashland ⁴PEG-150/Stearyl/SMDI copolymer supplied byRohm and Haas

The hair color compositions described herein may be formed as thickliquid, cream, gel, emulsion, foam, aerosol mousse or as a solid form towhich water is added to generate the oxidant and form a thickenedvehicle suitable for hair coloring. They may comprise in addition to theingredients indicated above further ingredients in order to furtherenhance the properties of the composition, including but not limited to:solvents; oxidative dyes, direct dyes; oxidizing agents; radicalscavengers; thickeners and or rheology modifiers; chelants; pH modifiersand buffering agents; carbonate ion sources; peroxymonocarbonate ionsources; anionic, cationic, nonionic, amphoteric or zwitterionicsurfactants, or mixtures thereof; anionic, cationic, nonionic,amphoteric or zwitterionic polymers, or mixtures thereof; fragrances;enzymes; dispersing agents; peroxide stabilizing agents; antioxidants;natural ingredients, e.g. proteins and protein compounds, and plantextracts; conditioning agents including silicones and cationic polymers,ceramides, preserving agents; and opacifiers and pearling agents (suchas titanium dioxide and mica). Some adjuvants referred to above, but notspecifically described below, which are suitable are listed in theInternational Cosmetics Ingredient Dictionary and Handbook, (8th ed.;The Cosmetics, Toiletry, and Fragrance Association). Particularly, vol.2, sections 3 (Chemical Classes) and 4 (Functions) are useful inidentifying specific adjuvants to achieve a particular purpose ormultipurpose. A few of these ingredients are discussed hereinbelow,whose disclosure is of course non-exhaustive.

Optional Ingredients

The hair color compositions described herein may comprise, in additionto the ingredients indicated above, optional ingredients in order tofurther enhance the properties of the composition.

Suitable optional ingredients include, but are not limited to: solvents;oxidizing agents; alkalizing agents; oxidative dye precursors, directdyes; chelants; radical scavengers; pH modifiers and buffering agents;thickeners and/or rheology modifiers; carbonate ion sources;peroxymonocarbonate ion sources; anionic, cationic, nonionic, amphotericor zwitterionic surfactants, and mixtures thereof; anionic, cationic,nonionic, amphoteric or zwitterionic polymers, and mixtures thereof;fragrances; enzymes; dispersing agents; peroxide stabilizing agents;antioxidants; natural ingredients (such as proteins, protein compounds,and plant extracts); conditioning agents (such as silicones and cationicpolymers); ceramides; preserving agents; opacifiers and pearling agents(such as titanium dioxide and mica); and mixtures thereof.

Suitable further ingredients referred to above, but not specificallydescribed below, are listed in the International Cosmetics IngredientDictionary and Handbook, (8th ed.; The Cosmetics, Toiletry, andFragrance Association). Particularly, vol. 2, sections 3 (ChemicalClasses) and 4 (Functions), which are useful in identifying specificadjuvants to achieve a particular purpose or multipurpose. A few ofthese ingredients are discussed hereinbelow, whose disclosure is ofcourse non-exhaustive.

Solvents

The hair color compositions described herein may further comprise asolvent. The solvent may be selected from water, or a mixture of waterand at least one organic solvent to dissolve the compounds that wouldnot typically be sufficiently soluble in water.

Suitable organic solvents include, but are not limited to: C1 to C4lower alkanols (such as ethanol, propanol, isopropanol); aromaticalcohols (such as benzyl alcohol and phenoxyethanol); polyols and polyolethers (such as carbitols, 2-butoxyethanol, propylene glycol, propyleneglycol monomethyl ether, diethylene glycol monoethyl ether, monomethylether, hexylene glycol, glycerol, ethoxy glycol, butoxydiglycol,ethoxydiglycerol, dipropyleneglocol, polygylcerol); propylene carbonate;and mixtures thereof.

In an embodiment, the solvent may be selected from the group consistingof water, ethanol, propanol, isopropanol, glycerol, 1,2-propyleneglycol, hexylene glycol, ethoxy diglycol, and mixtures thereof.

The composition may comprise water as a main ingredient, particularly ina total amount ranging from at least about 50%, alternatively from atleast about 60%, alternatively from at least about 70%, by weight of thetotal composition. In an embodiment, the composition may comprise atotal amount of organic solvents ranging from about 1% to about 30%, byweight of the total hair color composition.

Oxidizing Agent

The hair color composition described herein may comprise at least onesource of an oxidizing agent. Preferred oxidizing agents for use hereinare water soluble peroxygen oxidizing agents. Water-soluble peroxygenoxidizing agents are well known in the art and include, but are notlimited to, hydrogen peroxide, inorganic alkali metal peroxides such assodium periodate and sodium peroxide and organic peroxides such as ureaperoxide, melamine peroxide, and inorganic perhydrate salt bleachingcompounds, such as the alkali metal salts of perborates, percarbonates,perphosphates, persilicates, persulfates and the like. These inorganicperhydrate salts may be incorporated as monohydrates, tetrahydrates etc.Alkyl and aryl peroxides, and or peroxidases, oxidases, and uricases andtheir substrates may also be used. Mixtures of two or more suchoxidizing agents can also be used if desired. The oxidizing agents maybe provided in aqueous solution or as a powder which is dissolved priorto use. In an embodiment, the oxidizing agents may be selected from thegroup consisting of hydrogen peroxide, percarbonate, persulfates andcombinations thereof.

In an embodiment, the hair color composition may comprise from 0.1% to20% by weight, or from 1% to 15% by weight, or from 2% to 10% by weightof the oxidizing agent.

A potential oxidizing agent for use herein is a source ofperoxymonocarbonate ions formed in situ from a source of hydrogenperoxide and a hydrogen carbonate ion source. Moreover, this system isalso particularly effective in combination with a source of ammonia orammonium ions. Accordingly, any source of these peroxymonocarbonate ionsmay be used. Suitable sources for use herein include sodium, potassium,guanidine, arginine, lithium, calcium, magnesium, barium, ammonium saltsof carbonate, carbamate and hydrocarbonate ions and mixtures thereofsuch as sodium carbonate, sodium hydrogen carbonate, potassiumcarbonate, potassium hydrogen carbonate, guanidine carbonate, guanidinehydrogen carbonate, lithium carbonate, calcium carbonate, magnesiumcarbonate, barium carbonate, ammonium carbonate, ammonium hydrogencarbonate and mixtures thereof. Percarbonate salts may be used both asan oxidizing agent and as a source of carbonate ions. Preferred sourcesof carbonate ions, carbamate and hydrocarbonate ions are sodium hydrogencarbonate, potassium hydrogen carbonate, ammonium carbamate, andmixtures thereof.

The oxidizing agent may comprise from 0.1% to 15% by weight, or from 1%to 10% by weight, or from 1% to 8% by weight of a hydrogen carbonateion; and from 0.1% to 10% by weight, or from 1% to 7% by weight, or from2% to 5% by weight of the oxidizing agent of a source of hydrogenperoxide.

Alkalizing Agent

The hair color composition described herein may further comprise analkalizing agent as known in the art. Any alkalizing agent known in theart may be used such as ammonia, alkanolamines for examplemonoethanolamine, diethanolamine, triethanolamine, monopropanolamine,dipropanolamine, tripropanolamine, 2-amino-2-methyl-1,3-propanediol,2-amino-2-methyl-1-propanol, and2-amino-2-hydroxymethyl-1,3-propanediol, guanidium salts, alkali metaland ammonium hydroxides such as sodium hydroxide, alkali metal andammonium carbonates, and mixtures thereof. In an embodiment, thealkalizing agent may be ammonia and/or monoethanolamine.

The hair color compositions described herein may comprise from about0.1% to about 10%, preferably from about 0.5% to about 6%, morepreferably from about 1% to about 4% by weight of the alkalizing agentrelative to the total weight of the composition.

The hair colorant compositions described above may have a pH of from 7to 12, alternatively from 8 to 11. For embodiments comprising aperoxymonocarbonate ion, the pH may be up to and including pH 9.5,alternatively from 7.5 to 9.5, alternatively from 8.4 to 9.5,alternatively from 8.5 to 9.4, alternatively 9.0, and alternatively 9.3.

Any sub-components of the hair color compositions, such as a tintcomposition or an oxidizing composition, may have a different pH fromthe hair colorant composition. For example, if the tint compositioncomprises an alkalizing agent, the tint composition will have analkaline pH, such as higher than 7. In an embodiment, the oxidizingcomposition may comprise an acidic pH of less than 7.

When the hair color composition described herein is obtained by mixing adeveloper and a tint composition prior to use, the alkalizing agent isgenerally present in the tint composition.

Oxidative Dye Precursors

In addition to the direct dye compounds described herein, the hair colorcomposition may further comprise one or more oxidative dye precursors,which are usually classified either as primary intermediates (also knownas developers) or couplers (also known as secondary intermediates).Various couplers may be used with primary intermediates in order toobtain different shades. Oxidative dye precursors may be free bases orthe cosmetically acceptable salts thereof.

In an embodiment, the hair color composition may comprise a total amountof oxidative dye precursors ranging up to about 12%, alternatively fromabout 0.1% to about 10%, alternatively from about 0.3% to about 8%,alternatively from about 0.5% to about 6%, by weight of the totalcomposition.

Suitable primary intermediates include, but are not limited to:toluene-2,5-diamine, p-phenylenediamine, N-phenyl-p-phenylenediamine,N,N-bis(2-hydroxyethyl)-p-phenylenediamine,2-hydroxyethyl-p-phenylenediamine,hydroxypropyl-bis-(N-hydroxyethyl-p-phenylenediamine),2-methoxymethyl-p-phenylenediamine,2-(1,2-dihydroxyethyl)-p-phenylenediamine,2,2′-(2-(4-aminophenylamino)ethylazanediyl)diethanol,2-(2,5-diamino-4-methoxyphenyl)propane-1,3-diol,2-(7-amino-2H-benzo[b][1,4]oxazin-4(3H)-yl)ethanol,2-chloro-p-phenylenediamine, p-aminophenol, p-(methylamino)phenol,4-amino-m-cresol, 6-amino-m-cresol, 5-ethyl-o-aminophenol,2-methoxy-p-phenylenediamine, 2,2′-methylenebis-4-aminophenol,2,4,5,6-tetraminopyrimidine, 2,5,6-triamino-4-pyrimidinol,1-hydroxyethyl-4,5-diaminopyrazole sulfate,4,5-diamino-1-methylpyrazole, 4,5-diamino-1-ethylpyrazole,4,5-diamino-1-isopropylpyrazole, 4,5-diamino-1-butylpyrazole,4,5-diamino-1-pentylpyrazole, 4,5-diamino-1-benzylpyrazole,(2,3-diamino-6,7-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-onedimethanesulfonate), 4,5-diamino-1-hexylpyrazole,4,5-diamino-1-heptylpyrazole, methoxymethyl-1,4-diaminobenzene,N,N-bis(2-hydroxyethyl)-N-(4-aminophenyl)-1,2-diaminothane,2-[(3-aminopyrazolo[1,5-a]pyridin-2-yl)oxy]ethanol hydrochloride, saltsthereof and mixtures thereof.

Suitable couplers include, but are not limited to: resorcinol,4-chlororesorcinol, 2-chlororesorcinol, 2-methylresorcinol,4,6-dichlorobenzene-1,3-diol, 2,4-dimethylbenzene-1,3-diol,m-aminophenol, 4-amino-2-hydroxytoluene,2-methyl-5-hydroxyethylaminophenol, 3-amino-2,6-dimethylphenol,3-amino-2,4-dichlorophenol, 5-amino-6-chloro-o-cresol,5-amino-4-chloro-o-cresol, 6-hydroxybenzomorpholine,2-amino-5-ethylphenol, 2-amino-5-phenylphenol, 2-amino-5-methylphenol,2-amino-6-methylphenol, 2-amino-5-ethoxyphenol,5-methyl-2-(methylamino)phenol, 2,4-diaminophenoxyethanol,2-amino-4-hydroxyethylaminoanisole,1,3-bis-(2,4-diaminophenoxy)-propane,2,2′-(2-methyl-1,3-phenylene)bis(azanediyl)diethanol,benzene-1,3-diamine, 2,2′-(4,6-diamino-1,3-phenylene)bis(oxy)diethanol,3-(pyrrolidin-1-yl)aniline, 1-(3-(dimethylamino)phenyl)urea,1-(3-aminophenyl)urea, 1-naphthol, 2-methyl-1-naphthol,1,5-naphthalenediol, 2,7-naphthalenediol or1-acetoxy-2-methylnaphthalene, 4-chloro-2-methylnaphthalen-1-ol,4-methoxy-2-methylnaphthalen-1-ol, 2,6-dihydroxy-3,4-dimethylpyridine,2,6-dimethoxy-3,5-pyridinediamine,3-amino-2-methylamino-6-methoxypyridine, 2-amino-3-hydroxypyridine,2,6-diaminopyridine, pyridine-2,6-diol, 5,6-dihydroxyindole,6-hydroxyindole, 5,6-dihydroxyindoline,3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, 1,2,4-trihydroxybenzene,2-(benzo[d][1,3]dioxol-5-ylamino)ethanol (also known ashydroxyethyl-3,4-methylenedioxyaniline), and mixtures thereof.

When the hair color composition described herein is obtained by mixing atint composition and a developer composition, the primary intermediatesand couplers may be incorporated into the tint composition.

Additional Direct Dyes

The hair color composition may further comprise additional compatibledirect dyes, in an amount sufficient to provide additional coloring,particularly with regard to intensity. In an embodiment, the compositionmay comprise a total amount of direct dyes ranging from about 0.05% toabout 4%, by weight of the total composition.

Suitable direct dyes include but are not limited to: HC Yellow 17, HCBlue 18, HC Yellow 16, HC Red 18, Acid dyes such as Acid Yellow 1, AcidOrange 3, Acid Black 1, Acid Black 52, Acid Orange 7, Acid Red 33, AcidYellow 23, Acid Blue 9, Acid Violet 43, HC Blue 16, Acid Blue 62, AcidBlue 25, Acid Red 4; Basic Dyes such as Basic Brown 17, Basic Red 118,Basic Orange 69, Basic Red 76, Basic Brown 16, Basic Yellow 57, BasicViolet 14, Basic Blue 7, Basic Blue 26, Basic Red 2, Basic Blue 99,Basic Yellow 29, Basic Red 51, Basic Orange 31, Basic Yellow 87, BasicBlue 124,4-(3-(4-amino-9,10-dioxo-9,10-dihydroanthracen-1-ylamino)propyl)-4-methylmorpholin-4-ium-methylsulfate,(E)-1-(2-(4-(4,5-dimethylthiazol-2-yl)diazenyl)phenyl)(ethyl)amino)ethyl)-3-methyl-1H-imidazol-3-iumchloride,(E)-4-(2-(4-(dimethylamino)phenyl)diazenyl)-1-methyl-1H-imidazol-3-ium-3-yl)butane-1-sulfonate,(E)-4-(4-(2-methyl-2-phenylhydrazono)methyl)pyridinium-1-yl)butane-1-sulfonate,N,N-dimethyl-3-(4-(methylamino)-9,10-dioxo-4a,9,9a,10-tetrahydroanthracen-1-ylamino)-N-propylpropan-1-aminiumbromide; Disperse Dyes such as Disperse Red 17, Disperse Violet 1,Disperse Red 15, Disperse Black 9, Disperse Blue 3, Disperse Blue 23,Disperse Blue 377; Nitro Dyes such as1-(2-(4-nitrophenylamino)ethyl)urea,2-(4-methyl-2-nitrophenylamino)ethanol, 4-nitrobenzene-1,2-diamine,2-nitrobenzene-1,4-diamine, Picramic acid, HC Red No. 13,2,2′-(2-nitro-1,4-phenylene)bis(azanediyl)diethanol, HC Yellow No. 5, HCRed No. 7, HC Blue No. 2, HC Yellow No. 4, HC Yellow No. 2, HC OrangeNo. 1, HC Red No. 1, 2-(4-amino-2-chloro-5-nitrophenylamino)ethanol, HCRed No. 3, 4-amino-3-nitrophenol, 4-(2-hydroxyethylamino)-3-nitrophenol,2-amino-3-nitrophenol, 2-(3-(methylamino)-4-nitrophenoxy)ethanol,3-(3-amino-4-nitrophenyl)propane-1,2-diol, HC Yellow No. 11, HC VioletNo. 1, HC Orange No. 2, HC Orange No. 3, HC Yellow No. 9, HC Red No. 10,HC Red No. 11, 2-(2-hydroxyethylamino)-4,6-dinitrophenol, HC Blue No.12, HC Yellow No. 6, HC Yellow No. 12, HC Blue No. 10, HC Yellow No. 7,HC Yellow No. 10, HC Blue No. 9, 2-chloro-6-(ethylamino)-4-nitrophenol,6-nitropyridine-2,5-diamine, HC Violet No. 2,2-amino-6-chloro-4-nitrophenol, 4-(3-hydroxypropylamino)-3-nitrophenol,HC Yellow No. 13, 6-nitro-1,2,3,4-tetrahydroquinoxaline, HC Red No. 14,HC Yellow No. 15, HC Yellow No. 14,N2-methyl-6-nitropyridine-2,5-diamine,N1-allyl-2-nitrobenzene-1,4-diamine, HC Red No. 8, HC Green No. 1, HCBlue No. 14; Natural dyes such as Annato, Anthocyanin, Beetroot,Carotene, Capsanthin, Lycopene, Chlorophyll, Henna, Indigo, Cochineal;and mixtures thereof.

When the hair color composition is obtained by mixing a tint compositionand a developer composition, the additional direct dyes may beincorporated into the tint composition.

Chelants

The hair color composition described herein may further comprisechelants (also known as “chelating agent”, “sequestering agent”, or“sequestrant”) in an amount sufficient to reduce the amount of metalsavailable to interact with formulation components, particularlyoxidizing agents, more particularly peroxides. Chelants are well knownin the art and a non-exhaustive list thereof can be found in A E Martell& R M Smith, Critical Stability Constants, Vol. 1, Plenum Press, NewYork & London (1974) and A E Martell & R D Hancock, Metal Complexes inAqueous Solution, Plenum Press, New York & London (1996), bothincorporated herein by reference.

In an embodiment, the hair color composition may comprise a total amountof chelants ranging from at least about 0.01%, alternatively from about0.01% to about 5%, alternatively from about 0.25% to about 3%,alternatively from about 0.5% to about 1%, by weight of the totalcomposition.

Suitable chelants include, but are not limited to: carboxylic acids(such as aminocarboxylic acids), phosphonic acids (such asaminophosphonic acids), polyphosphoric acids (such as linearpolyphosphoric acids), their salts thereof, and mixtures thereof. By“salts thereof”, it is meant—in the context of chelants—all saltscomprising the same functional structure as the chelant they arereferring to and including alkali metal salts, alkaline earth salts,ammonium salts, substituted ammonium salts, and mixtures thereof;alternatively sodium salts, potassium salts, ammonium salts, andmixtures thereof; alternatively monoethanolammonium salts,diethanolammonium salts, triethanolammonium salts, and mixtures thereof.

Suitable aminocarboxylic acid chelants comprise at least one carboxylicacid moiety (—COOH) and at least one nitrogen atom. Suitableaminocarboxylic acid chelants include, but are not limited to:diethylenetriamine pentaacetic acid (DTPA), ethylenediamine disuccinicacid (EDDS), ethylenediamine diglutaric acid (EDGA),2-hydroxypropylenediamine disuccinic acid (HPDS),glycinamide-N,N′-disuccinic acid (GADS), ethylenediamine-N—N′-diglutaricacid (EDDG), 2-hydroxypropylenediamine-N—N′-disuccinic acid (HPDDS),ethylenediaminetetraacetic acid (EDTA), ethylenedicysteic acid (EDC),ethylenediamine-N—N′-bis(ortho-hydroxyphenyl acetic acid) (EDDHA),diaminoalkyldi(sulfosuccinic acids) (DDS),N,N′-bis(2-hydroxybenzyl)ethylenediamine-N,N′-diacetic acid (HBED),their salts thereof, and mixtures thereof. Other suitableaminocarboxylic type chelants include, but are not limited to:iminodiacetic acid derivatives such as N-2-hydroxyethyl N,N diaceticacid or glyceryl imino diacetic acid, iminodiaceticacid-N-2-hydroxypropyl sulfonic acid and aspartic acid N-carboxymethylN-2-hydroxypropyl-3-sulfonic acid, β-alanine-N,N′-diacetic acid,aspartic acid-N,N′-diacetic acid, aspartic acid-N-monoacetic acid andiminodisuccinic acid chelants, ethanoldiglycine acid, their saltsthereof, their derivatives thereof, and mixtures thereof. Furthersuitable aminocarboxylic type chelants include, but are not limited to:dipicolinic acid, 2-phosphonobutane-1,2,4-tricarboxylic acid, theirsalts thereof, their derivatives thereof, and mixtures thereof.

Suitable aminophosphonic acid chelants comprise an aminophosphonic acidmoiety (—PO3H2) or its derivative—PO3R2, wherein R₂ is a C₁ to C₆ alkylor aryl radical and salts thereof. Suitable aminophosphonic acidchelants include, but are not limited to: aminotri-(1-ethylphosphonicacid), ethylene-diaminetetra-(1-ethylphosphonic acid),aminotri-(1-propylphosphonic acid), aminotri-(isopropylphosphonic acid),their salts thereof, and mixtures thereof; alternativelyaminotri-(methylenephosphonic acid),ethylene-diamine-tetra-(methylenephosphonic acid) (EDTMP) anddiethylene-triamine-penta-(methylenephosphonic acid) (DTPMP), theirsalts thereof, their derivatives thereof, and mixtures thereof.

Suitable alternative chelants include, but are not limited to:polyethyleneimines, polyphosphoric acid chelants, etidronic acid,methylglycine diacetic acid, N-(2-hydroxyethyl)iminodiacetic acid,minodisuccinnic acid, N,N-Dicarboxymethyl-L-glutamic acid,N-lauroyl-N,N′,N″-ethylenediamine diacetic acid, their salts thereof,their derivatives thereof, and mixtures thereof.

In a specific embodiment, the composition comprises a chelant selectedfrom the group consisting of diethylenetriamine-N,N′,N″-polyacids,diethylenetriaminepentaacetic acid (DTPA),diethylenetriaminepenta(methylene phosphonic acid) (DTPMP),diamine-N,N′-dipolyacid, monoamine monoamide-N,N′-dipolyacid,ethylenediaminedisuccinic acid (EDDS), their salts thereof, theirderivatives thereof, and mixtures thereof; alternativelyethylenediaminedisuccinic acid (EDDS).

When the hair color composition is obtained by mixing a tint compositionand a developer composition, the chelants may be incorporated in thetint composition and/or in the developer composition. A chelant may bepresent in the developer composition for stability.

Radical Scavengers

The hair color compositions described herein may comprise a radicalscavenger. As used herein the term radical scavenger refers to a speciesthat can react with a radical, to convert the radical species by aseries of fast reactions to an unreactive or less reactive species. Theradical scavenger is also preferably selected such that it is not anidentical species as the alkalising agent and is present in an amountsufficient to reduce the damage to the hair during thecolouring/bleaching process. The compositions of the present inventioncomprise a radical scavenger from about 0.1% to about 10%, preferablyfrom about 1% to about 7% by weight of the radical scavenger relative tothe total weight of the composition.

Suitable radical scavengers for use herein may be selected from theclasses of alkanolamines, amino sugars, amino acids, esters of aminoacids and mixtures thereof. Suitable compounds include3-substituted-pyrazol-5-ones, 3-carboxy-1H-pyrazol-5-one,3-methyl-1-phenyl-pyrazol-5-one, 3-methyl-1-p-tolyl-pyrazol-5-one,3-methyl-1-(4-sulfophenyl)-pyrazol-5-one,3-methyl-1-(4-sulfoamidophenyl)-pyrazol-5-one,3-methyl-1-(3-sulfophenyl)-pyrazol-5-one,3-methyl-1-(3-sulfoamidophenyl)-pyrazol-5-one,3-methyl-1-(2-chloro-5-sulfophenyl)-pyrazol-5-one,3-methyl-1-(2,5-dichloro-4-sulfophenyl)-pyrazol-5-one,3-methyl-1-(4-chlorophenyl)-pyrazol-5-one,3-methyl-1-(4-carboxyphenyl)-pyrazol-5-one,3-carboxy-1-phenyl-pyrazol-5-one,3-carboxy-1-(4-sulfophenyl)-pyrazol-5-one, 1,3-diphenyl-pyrazol-5-one,methyl pyrazol-5-one-3-carboxylate, 3-amino-1-propanol,4-amino-1-butanol,5-amino-1-pentanol, 1-amino-2-propanol,1-amino-2-butanol, 1-amino-2-pentanol, 1-amino-3-pentanol,1-amino-4-pentanol, 3-amino-2-methylpropan-1-ol,1-amino-2-methylpropan-2-ol, 3-aminopropane-1,2-diol, glucosamine,N-acetylglucosamine, glycine, arginine, lysine, proline, glutamine,histidine, sarcosine, serine, glutamic acid, tryptophan, or mixturesthereof, or the salts, such as the potassium, sodium, or ammonium saltsthereof, or mixtures thereof. In some embodiments, the inventivecompositions may comprise glycine, sarcosine, lysine, serine,2-methoxyethylamine, glucosamine, glutamic acid, morpholine, piperidine,ethylamine, 3-amino-1-propanol, or mixtures thereof.

pH Modifiers and Buffering Agents

The hair color compositions described herein may further comprise, inaddition to the alkalizing agent discussed above, a pH modifier and/orbuffering agent in an amount that is sufficiently effective to adjustthe pH of the composition to fall within a range from about 3 to about13, alternatively from about 8 to about 12, alternatively from about 9to about 11.

Suitable pH modifiers and/or buffering agents include, but are notlimited to: ammonia; alkanolamides (such as monoethanolamine,diethanolamine, triethanolamine, monopropanolamine, dipropanolamine,tripropanolamine, tripropanolamine, 2-amino-2-methyl-1-propanol,2-amino-2-hydroxymethyl-1,3,-propandiol); guanidium salts; alkali metaland ammonium hydroxides and carbonates; and mixtures thereof.

Further pH modifiers and/or buffering agents include, but are notlimited to: sodium hydroxide; ammonium carbonate; acidulents (such asinorganic and inorganic acids including for example phosphoric acid,acetic acid, ascorbic acid, citric acid or tartaric acid, hydrochloricacid); and mixtures thereof.

Thickeners and/or Rheology Modifiers

The hair color compositions described herein may further comprise athickener in an amount sufficient to provide the composition with aviscosity so that it can be readily applied to the hair without undulydripping off the hair and causing mess.

In an embodiment, the hair color compositions may comprise a totalamount of thickeners ranging from at least about 0.1%, alternatively atleast about 1%, alternatively at least about 10%, alternatively at leastabout 20%, by weight of the total composition.

Suitable thickeners include, but are not limited to: associativepolymers, polysaccharides, non-associative polycarboxylic polymers, andmixtures thereof.

As used herein, the expression “associative polymers” means amphiphilicpolymers comprising both hydrophilic units and hydrophobic units, forexample, at least one C8 to C30 fatty chain and at least one hydrophilicunit. Associative polymers are capable of reversibly combining with eachother or with other molecules. Suitable associative thickeners include,but are not limited to: nonionic amphiphilic polymers comprising atleast one hydrophilic unit and at least one fatty-chain unit; anionicamphiphilic polymers comprising at least one hydrophilic unit and atleast one fatty-chain unit; cationic amphiphilic polymers comprising atleast one hydrophilic unit and at least one fatty-chain unit; andamphoteric amphiphilic polymers comprising at least one hydrophilic unitand at least one fatty-chain unit, and mixtures thereof.

Suitable nonionic amphiphilic polymers comprising at least one fattychain and at least one hydrophilic unit include, but are not limited to:celluloses modified with groups comprising at least one fatty chain(such as hydroxyethylcelluloses modified with groups comprising at leastone fatty chain chosen from alkyl, alkenyl and alkylaryl groups);hydroxypropyl guars modified with groups comprising at least one fattychain; polyether urethanes comprising at least one fatty chain (such asC8-C30 alkyl or alkenyl groups); copolymers of vinylpyrrolidone and offatty-chain hydrophobic monomers; copolymers of C1-C6 alkyl acrylates ormethacrylates and of amphiphilic monomers comprising at least one fattychain; copolymers of hydrophilic acrylates or methacrylates and ofhydrophobic monomers comprising at least one fatty chain, and mixturesthereof. Commercially available anionic materials include those sold asSepigel 305 by Seppic.

Suitable nonionic amphiphilic polymers comprising at least onehydrophilic unit and at least one fatty-chain unit include, but are notlimited to: those polymers comprising at least one fatty-chain allylether unit and at least one hydrophilic unit comprising an ethylenicunsaturated anionic monomeric unit (such as a vinylcarboxylic acid unit,particularly a unit chosen from units derived from acrylic acids,methacrylic acids, and mixtures thereof), wherein the fatty-chain allylether unit corresponds to the monomer of formula (XV) belowCH2=C(R1)CH2OBnR  (XV)in which R1 is chosen from H and CH3, B is an ethyleneoxy radical, n ischosen from zero and integers ranging from 1 to 100, R is chosen fromhydrocarbon-based radicals chosen from alkyl, alkenyl, arylalkyl, aryl,alkylaryl and cycloalkyl radicals, comprising from 8 to 30 carbon atoms,and, further, for example, from 10 to 24 carbon atoms and even further,for example, from 12 to 18 carbon atoms.

Suitable anionic amphiphilic polymers include, but are not limited to:those polymers comprising at least one hydrophilic unit of unsaturatedolefinic carboxylic acid type, and at least one hydrophobic unit of thetype such as a (C8-C30) alkyl ester or (C8-C30) oxyethylenated alkylester of an unsaturated carboxylic acid, wherein the hydrophilic unit ofunsaturated olefinic carboxylic acid type corresponds to, for example,the monomer of formula (XVI) belowCH2=C(R1)COOH  (XVI)in which R1 is chosen from H, CH3, C2H5 and CH2COOH (i.e. acrylic acid,methacrylic, ethacrylic and itaconic acid units); and wherein thehydrophobic unit of the type such as a (C8-C30) alkyl ester or (C8-C30)oxyethylenated alkyl ester of an unsaturated carboxylic acid correspondsto, for example, the monomer of formula (XVII) belowCH2=C(R1)COOBnR2  (XVII)in which R1 is chosen from H, CH3, C2H5 and CH2COOH (i.e. acrylate,methacrylate, ethacrylate and itaconate units), B is an ethyleneoxyradical, n is chosen from zero and integers ranging from 1 to 100, R2 ischosen from C8-C30 alkyl radicals, for example, C12-C22 alkyl radical.Anionic amphiphilic polymers may further be cross-linked. Thecrosslinking agent can be a monomer comprising a group (XVIII) belowCH2=C<  (XVIII)with at least one other polymerizable group whose unsaturated bonds arenot conjugated with respect to one another. Mention may be made, forexample, of polyallyl ethers such as polyallylsucrose and polyallylpentaerythritol.

Suitable cationic amphiphilic polymers include, but are not limited to:quaternized cellulose derivatives and polyacrylates comprising aminoside groups. The quaternized cellulose derivatives are, for example,chosen from quaternized celluloses modified with groups comprising atleast one fatty chain, such as alkyl, arylalkyl and alkylaryl groupscomprising at least 8 carbon atoms, and mixtures thereof, quaternizedhydroxyethylcelluloses modified with groups comprising at least onefatty chain, such as alkyl, arylalkyl and alkylaryl groups comprising atleast 8 carbon atoms, and mixtures thereof. The alkyl radicals borne bythe above quaternized celluloses and hydroxyethylcelluloses, forexample, contain from 8 to 30 carbon atoms. The aryl radicals, forexample, are chosen from phenyl, benzyl, naphthyl and anthryl groups.

Suitable amphoteric amphiphilic polymers comprising at least onehydrophilic unit and at least one fatty-chain unit, may be made, forexample, of methacrylamidopropyltrimethylammonium chloride/acrylicacid/C8-C30 alkyl methacrylate copolymers, wherein the alkyl radical is,for example, a stearyl radical.

In an embodiment, the associative polymers may comprise at least onehydrophilic unit which is unsaturated carboxylic acid or itsderivatives, and at least one hydrophobic unit which is a C8 to C30alkyl ester or oxyethylenated C8-C30 alkyl ester of unsaturatedcarboxylic acid. The unsaturated carboxylic acid is preferably acrylicacid, methacrylic acid or itaconic acid. Commercially availablematerials include those sold as Aculyn-22 by Rohm & Haas; Permulen TR1,Carbopol 2020, Carbopol Ultrez-21/-30 by Noveon, Structure 2001/3001 byNational Starch. Other preferred associative polymers include polyetherpolyurethane, commercially available as Aculyn-44/-46 by Rohm and Haas.Further preferred associative polymers include cellulose modified withgroups comprising at least one C8-C30 fatty chain, commerciallyavailable under the trade name Natrosol Plus Grade 330 CS by Aqualon.

Suitable non-associative cross-linked polycarboxylic polymers include,but are not limited to: cross-linked acrylic acid homopolymers,copolymers of acrylic or (meth)acrylic acid and of C1-C6 alkyl acrylateor (meth)acrylate, and mixtures thereof. Commercially availablematerials include those sold as Carbopol 980/981/954/1382/2984/5984 byNoveon, Synthalen M/Synthalen L/Synthalen K/Synthalen CR by 3V,Aculyn-33 by Rohm and Haas.

Suitable polysaccharides include, but are not limited to: glucans,modified and unmodified starches (such as those derived, for example,from cereals, for instance wheat, corn or rice, from vegetables, forinstance yellow pea, and tubers, for instance potato or cassaya),amylose, amylopectin, glycogen, dextrans, celluloses and derivativesthereof (methylcelluloses, hydroxyalkylcelluloses, ethylhydroxyethylcelluloses, and carboxymethylcelluloses), mannans, xylans,lignins, arabans, galactans, galacturonans, chitin, chitosans,glucuronoxylans, arabinoxylans, xyloglucans, glucomannans, pectic acidsand pectins, alginic acid and alginates, arabinogalactans, carrageenans,agars, glycosaminoglucans, gum arabics, gum tragacanths, ghatti gums,karaya gums, carob gums, galactomannans, such as guar gums, and nonionicderivatives thereof (hydroxypropyl guar) and bio-polysaccharides, suchas xanthan gums, gellan gums, welan gums, scleroglucans, succinoglycans,and mixtures thereof. Suitable polysaccharides are described in“Encyclopedia of Chemical Technology”, Kirk-Othmer, Third Edition, 1982,volume 3, pp. 896-900, and volume 15, pp. 439-458, in “Polymers inNature” by E. A. MacGregor and C. T. Greenwood, published by John Wiley& Sons, Chapter 6, pp. 240-328, 1980, and in “IndustrialGums—Polysaccharides and their Derivatives”, edited by Roy L. Whistler,Second Edition, published by Academic Press Inc., all three beingincorporated herein by reference. A preferred polysaccharide is abio-polysaccharide, particularly bio-polysaccharides selected fromxanthan gum, gellan gum, welan gum, scleroglucan or succinoglycan;commercially available as Keltrol® T by Kelco and Rheozan® by RhodiaChimie. Another preferred polysaccharide is hydroxypropyl starchderivative, particularly hydroxypropyl starch phosphate, commerciallyavailable as Structure XL® by National Starch, a hydrophobicallymodified cellulose derivative, commercially available as Structure® Cel500 HM by AkzoNobel.

Commercially available salt-tolerant thickeners include, but not limitedto: xanthan, guar, hydroxypropyl guar, scleroglucan, methyl cellulose,ethyl cellulose (commercially available as Aquacote), hydroxyethylcellulose (Natrosol), carboxymethyl cellulose, hydroxypropylmethylcellulose, microcrystalline cellulose, hydroxybutylmethyl cellulose,hydroxypropyl cellulose (Klucel), hydroxyethyl ethyl cellulose, cetylhydroxyethyl cellulose (Natrosol Plus 330), polyvinylpyrrolidone(Povidone, FlexiThix™), Acrylates/Ceteth-20 Itaconate Copolymer(Structure 3001), hydroxypropyl starch phosphate (Structure ZEA),polyethoxylated urethanes or polycarbamyl polyglycol ester such asPEG-150/Decyl/SMDI copolymer (Aculyn 44), PEG-150/Stearyl/SMDI copolymer(Aculyn 46), trihydroxystearin (Thixcin), acrylates copolymer (Aculyn33) or hydrophobically modified acrylate copolymers (such asAcrylates/Steareth-20 Methacrylate Copolymer as Aculyn 22),acrylates/steareth-20 methacrylate crosspolymer (Aculyn 88),acrylates/vinyl neodecanoate crosspolymer (Aculyn 38),acrylates/beheneth-25 methacrylate copolymer (Aculyn 28),acrylates/C10-30 alkyl acrylate crosspolymer (Carbopol ETD 2020),non-ionic amphophilic polymers comprising at least one fatty chain andat least one hydrophilic unit selected from polyether urethanescomprising at least one fatty chain, blends of Ceteth-10 phosphate,Dicetyl phosphate and Cetearyl alcohol (available as Crodafos CES), andmixtures thereof.

Salt

In an embodiment, cosmetically acceptable salt, such as ammonium, sodiumor potassium salts with appropriate counter ions, may be added to thehair color compositions described herein to act as leveling agents tominimize patchy coloring results.

Carbonate Ion Sources

The hair color compositions described herein may further comprise asource of carbonate ions, carbamate ions, hydrogen carbonate ions, andmixtures thereof in a sufficient amount to reduce damage to the hairduring the coloring process.

In an embodiment, the hair color compositions may comprise a totalamount of a carbonate ion source ranging from about 0.1% to about 15%,alternatively from about 0.1% to about 10%, alternatively from about 1%to about 7%, by weight of the total composition.

Suitable carbonate ion sources include, but are not limited to: sodiumcarbonate, sodium hydrogen carbonate, potassium carbonate, potassiumhydrogen carbonate, guanidine carbonate, guanidine hydrogen carbonate,lithium carbonate, calcium carbonate, magnesium carbonate, bariumcarbonate, ammonium carbonate, ammonium hydrogen carbonate and mixturesthereof; alternatively sodium hydrogen carbonate, potassium hydrogencarbonate, and mixtures thereof; alternatively ammonium carbonate,ammonium hydrogen carbonate, and mixtures thereof.

Conditioning Agents

The hair color compositions described herein may further comprise aconditioning agent, and/or be used in combination with a compositioncomprising a conditioning agent.

In an embodiment, the hair color compositions may comprise a totalamount of conditioning agents ranging from about 0.05% to about 20%,alternatively from about 0.1% to about 15%, alternatively from about0.2% to about 10%, alternatively from about 0.2% to about 2%,alternatively from about 0.5% to 2%, by weight of the total composition.The conditioning agent may be included in a separate pre- and/orpost-treatment composition.

Suitable conditioning agents include, but are not limited to: silicones,aminosilicones, fatty alcohols, polymeric resins, polyol carboxylic acidesters, cationic polymers, cationic surfactants, insoluble oils and oilderived materials and mixtures thereof. Additional conditioning agentsinclude mineral oils and other oils such as glycerin and sorbitol.

Particularly useful conditioning materials may be cationic polymers.Conditioners of cationic polymer type can be chosen from thosecomprising units of at least one amine group chosen from primary,secondary, tertiary and quaternary amine groups that may either formpart of the main polymer chain, or be borne by a side substituent thatis directly attached to the main polymer chain, described hereinafter.

Suitable silicones include, but are not limited to: polyalkylsiloxaneoils, linear polydimethylsiloxane oils containing trimethylsilyl orhydroxydimethylsiloxane endgroups, polymethylphenylsiloxane,polydimethylphenylsiloxane or polydimethyldiphenylsiloxane oils,silicone resins, organofunctional siloxanes having in their generalstructure one or a number of organofunctional group(s), the same ordifferent, attached directly to the siloxane chain and mixtures thereof.Said organofunctional group(s) may be selected from: polyethyleneoxyand/or polypropyleneoxy groups, (per)fluorinated groups, thiol groups,substituted or unsubstituted amino groups, carboxylate groups,hydroxylated groups, alkoxylated groups, quaternium ammonium groups,amphoteric and betaine groups. The silicone can either be used as a neatfluid or in the form of a pre-formed emulsion. Suitable silicones alsoinclude: silicones containing groups that may be ionized into cationicgroups, for example aminosilicones containing at least 10 repeatingsiloxane (Si(CH₃)₂—O) units within the polymer chain, with eitherterminal, graft, or a mixture of terminal and graft aminofunctionalgroups. Example functional groups are not limited toaminoethylaminopropyl, aminoethylaminoisobutly, aminopropyl. In the caseof graft polymers, the terminal siloxane units can be (CH₃)₃Si—O,R₁₂(CH₃)₂Si—O, where R₁₂ can be either OH or OR₁₃, where R₁₃ is a C1-C8alkyl group, or a mixture of both terminal groups. These silicones arealso available as preformed emulsions. Commercially availableaminosilicones include those sold as DC-2-8566, DC 7224, DC-2-8220 byDow Corning; SF1708, SM2125 by GE Silicones; Wacker Belsil ADM 653/ADM1100/ADM 1600/ADM 652/ADM 6057E/ADM 8020 by Wacker Silicones; DC929,DC939, DC949 by Dow Corning; SM2059 by GE Silicones. Suitableaminosilicones may also contain additional functional groups,particularly additional functional groups including polyoxyalkylene, thereaction product of amines and carbinols, and alky chains. Commerciallyavailable materials are known as methoxy PEG/PPG-7/3 AminopropylDimethicone (e.g. Abil Soft AF100, by Degussa), or as Bis(C13-15Alkoxy)PG Amodimethicone (e.g. DC 8500, by Dow Corning).

Suitable cationic polymers include, but are not limited to: polymerscomprising units of at least one amine group chosen from primary,secondary, tertiary and quaternary amine groups that may either formpart of the main polymer chain or be borne by a side substituent that isdirectly attached to the main polymer chain. Such cationic polymersgenerally have a number average molecular mass ranging from about 500 toabout 5×10⁶, alternatively from about 1000 to about 3×10⁶. Preferablythe cationic polymers are selected from polymers of the polyamine,polyamino amide and polyquaternary ammonium type.

Suitable polymers of the polyamine, polyamino amide and polyquaternaryammonium type include, but are not limited to:

1) Homopolymers and copolymers derived from acrylic or methacrylicesters or amides. Copolymers of these polymers may also comprise atleast one unit derived from comonomers which may be chosen from thefamily of acrylamides, methacrylamides, diacetone acylamides,acrylamides and methacrylicamides substituted on the nitrogen with atleast one group chosen from lower (C1-C4) alkyls, acrylic andmethacrylic acids and esters thereof, vinlylactams such asvinlypyrrolidone and vinylcaprolactam, and vinyl esters. Suitableexamples include copolymers of acrylamide and ofmethacryloyloxyethyltrimethylammonium methosulfate, including polymersknown as Polyquaternium-5 (e.g. commercially available under the tradename Reten 210/220/230/240/1104/1105/1006 by Hercules; Merquat 5/5 SF byNalco); copolymers of vinylpyrrolidone and dimethylaminopropylmethacrylamide, including polymers known as Polyquaternium-28 (e.g.Gafquat HS-100 by ISP); coplolymers of vinyl pyrrolidone anddialkyaminoalkyl acrylates or methactylates, including polymers known asPolquaternium-11 (see Gafquat 440/734/755/755N by ISP; Luviquat PQ11 PMby BASF; Polyquat-11 SL by Sino Lion); copolymers vinylpyrrolidone,dimethylaminopropyl methacrylamide and methacryloylaminopropyllauryldimonium chloride, including polymers known as polyquaternium-55(e.g. Styleze W-20 by ISP); copolymers of acrylic acid, acrylamide andmethacrylamidopropyltrimonium chloride, including polymers known asPolyquaternium-53 (e.g. Merquat 2003 by Nalco); copolymers ofdimethyaminopropylacrylate (DMAPA), acrylic acid and acrylonitrogens anddiethyl sulphate, including polymers known as Polyquaternium-31 (e.g.Hypan QT100 by Lipo); copolymers of acrylamide,acrylamidopropyltrimonium chloride, 2-amidopropylacrylamide sulfonate,and dimethyaminopropylacrylate (DMAPA), including polymers known aspolyquaternium-43 (e.g. Bozequat 4000 by Clairant); copolymers ofacrylic acid, methylacrylate and methacrylamidopropyltrimonium chloride,including polymers known as Polyquaternium-47 (e.g. Merquat 2001/2001Nby Nalco); copolymers of methacryloyl ethyl betaine, 2-hydroxyethylmethacrylate and methacryloyl ethyl trimethyl ammonium chloride,including polymers known as Polyquaternium-48 (e.g. Plascize L-450 byGoo Chemical); copolymers of acrylic acid diallyl dimethyl ammoniumchloride and acrylamide, including polymers known as polyquaternium-39(e.g. Merquat 3330/3331 by Nalco). Further suitable examples includecopolymers of methacrylamide methacrylamido-propyltrimonium andmethacryloylethyltrimethyl ammonium chloride and their derivatives,either homo or copolymerised with other monomers, including polymersknown as Polyquaternium-8, Polyquaternium-9, Polyquaternium-12,Polyquaternium-13 Polyquaternium-14, Polyquaternium-15 (e.g. Rohagit KF720 F by Rohm), Polyquaternium-30 (e.g. Mexomere PX by Chimex),Polyquaternium-33, Polyquaternium-35, Polyquaternium-36 (e.g. Plex 3074L by Rhon), Polyquaternium 45 (e.g. Plex 3073L by Rohn), Polyquaternium49 (e.g. Plascize L-440 by Goo Chemicals), Polyquaternium 50 (e.g.Plascize L-441 by Goo Chemicals), Polyquaternium-52.

2) Cationic polysaccharides, such as cationic celluloses and cationicgalactomannan gums. Among the cationic polysaccharides that maybementioned, for example, are cellulose ether derivatives comprisingquaternary ammonium groups and cationic cellulose copolymers orcellulose derivatives grafted with a water-soluble quaternary ammoniummonomer and cationic galactomannan gums. Suitable examples includecopolymers of hydroxyethylcelluloses and diallyldimethyl ammoniumchlorides, including polymers known as Polyquaternium-4 (e.g. Celquat L200 and Celquat H 100 by National Starch); copolymers ofhydroxyethylcelluloses and a trimethyl ammonium substituted epoxide,including polymers known as Polyquaternium-10 (e.g. AECPolyquaternium-10 by A&E Connock; CatinalC-100/HC-35/HC-100/HC-200/LC-100/LC-200 by Toho; Celquat SC-240C/SC-230Mby National Starch; Dekaquat 400/3000 by Dekker; Leogard GP by AkzoNobel; RITA Polyquat 400/3000 by RITA; UCARE PolymerJR-125/JR-400/JR-30M/LK/LR 400/LR 30M by Amerchol); copolymers ofhydroxyethylcelluloses and lauryl dimethyl ammonium substitutedepoxides, including polymers known as Polyquaternium-24 (e.g. Quatrisoftpolymer LM-200 by Amerchol); derivatives of hydroxypropyl guar,including polymers as guar hydroxypropyltrimonium chloride (e.g. CatinalCG-100, Catinal CG-200 by Toho; Cosmedia Guar C-261N, Cosmedia GuarC-261N, Cosmedia Guar C-261N by Cognis; DiaGum P 5070 by FreedomChemical Diamalt; N-Hance Cationic Guar by Hercules/Aqualon; Hi-Care1000, Jaguar C-17, Jaguar C-2000, Jaguar C-13S, Jaguar C-14S, JaguarExcel by Rhodia; Kiprogum CW, Kiprogum NGK by Nippon Starch);hydroxypropyl derivatives of guar hydroxypropyltrimonium chloride,including polymers known as hydroxypropyl guar hydroxypropyltrimoniumchloride (e.g. Jaguar C-162 by Rhodia).

3) Polyamino amide derivatives resulting from the condensation ofpolyalkylene polyamines with polycarboxylic acids followed by alkylationwith difunctional agents. Among the derivative, mention may be made forexample to adipic acid/dimethylaminohydroxypropyl/diethylenetriamine.

4) Polymers obtained by reaction of a polyalkylene polyamine comprisingtwo primary amines groups and at last one secondary amine group with adecarboxylic acid chosen from diglycolic acids and saturated aliphaticdicarboxylic acids comprising from 3 to 8 carbon atoms. Suitableexamples include the polymer adipic acid/epxoypropyl/diethylenetriamine.

5) Cyclopolymers of dialkdiallylamine or of dialkyldiallyammonium,including: Dimethyldiallyammonium chloride polymers, including polymersknown as Polyquaternium-6 (e.g. Merquat 100 by Nalco; Mirapol 100 byRhodia; Rheocare CC6 by Cosmetic Rheologies; AEC polyquaternium-6 by A&EConnock; Agequat 400 by CPS; Conditioner P6 by 3V Inc.; Flocare C106 bySNF; Genamin PDAC by Clariant; Mackernium 006 by McIntyre); copolymersof acrylamides and dimethyldiallylammonium chlorides monomers, includingpolymers known as Polyquaternium-7 (e.g. AEC Polyquaternium-7 by A&EConnock; Agequat-5008/C-505 by CPS; Conditioner P7 by 3V Inc.; Flocare C107 by SNF; Mackernium 007/007S by McIntyre; ME Polymer 09W by Toho;Merquat 550/2200/S by Nalco; Mirapol 550 by Rhodia; Rheocare CC7/CCP7 byCosmetic Rheologies; Salcare HSP-7/SC10/Super 7 by Ciba); copolymers ofdimethyldiallylammoniumchlorides and acrylic acids, including polymersknown as polyquaternary-22 (e.g. Merquat 280/Merquat 295 by Nalco).

6) Quaternary diammonium polymers comprising repeat units correspondingto [—N+(R1)(R2)-A1-N+(R3)(R4)-B1-][2X−], in which R1, R2, R3 and R4,which may be identical or different, are chosen from aliphatic,alicyclic and arylaliphatic radicals comprising from 1 to 20 carbonatoms and from lower hydroxyalkylaliphatic radicals, or R1, R2, R3 andR4, together or separately, constitute, with the nitrogen atoms to whichthey are attached, heterocycles optionally comprising a secondheteroatom other then nitrogen, or R1, R2, R3 and R4, are chosen fromliner or branched C1-C6 alkyl radicals substituted with at least onegroup chosen from nitrile, ester, acyl and amide groups and groups of—CO—O—R5-D and —CO—NH—R5-D wherein R5 is chosen from alkylene groups andD is chosen from quaternary ammonium groups. A1 and B1, which may beidentical or different, are chosen from linear and branched, saturatedor unsaturated polymethylene groups comprising 2 to 20 carbon atoms. Thepolymethylene groups may comprise, linked to or intercalated in the mainring, at least one entity chosen from aromatic rings, oxygen and sulphuratoms and sulphoxide, sulphone, disulphide, amino, alkylamino, hydroxyl,quaternary, ammonium, ureido, amide and ester groups, and X− is an anionderived from inorganic and organic acids. D is chosen from a glycolresidue, a bis-secondary diamine residue, a bis-primary diamine residueor a ureylene group. Suitable examples include polymers known asHexadimethrine chloride, where R1, R2, R3 and R4 are each methylradicals, Al is (CH2)3 and B1 is (CH2)6 and X=Cl; as polyquaternium-34where R1 and R2 are ethyl radicals and R3 and R4 are methyl radicals andAl is (CH2)3 and B1 is (CH2)₃ and X=Br (e.g. Mexomere PAX by Chimax).

7) Polyquaternary ammonium polymers comprising repeating units offormula[—N+(R6)(R7)-(CH2)r-NH—CO—(CH2)q-(CO)t-NH—(CH2)s-N+(R8)(R9)-A-][2X−], inwhich R6, R7, R8 and R9 which may be identical or different, are chosenfrom a hydrogen atom and a methyl, ethyl, propyl, hydroxyethyl,hydroxypropyl, and —CH2CH2(OCH2CH2)pOH radicals, wherein p is equal to 0or an integer ranging from 1 to 6, wherein R6, R7, R8 and R9 do not allsimultaneously represent a hydrogen atom. R and s which maybe identicalor different are each an integer ranging from 1 to 6, q is equal to 0 oran integer ranging from 1 to 34 and X− is anion such as a halide. T isan integer chosen to be equal to 0 or 1. A is chosen from divalentradicals such as —CH2-CH2-O—CH2-CH2-. Suitable examples include:polymers known as polyquaternium-2, where r=s=3, q=0, t=0, R6, R7, R8and R9 are methyl groups, and A is —CH2-CH2-O—CH2-CH2 (e.g. Ethpol PQ-2from Ethox; Mirapol A-15 by Rhodia); as polyquaternium-17 where r=s=3,q=4, t=1 R6, R7, R8 and R9 are methyl groups, and A is—CH2-CH2-O—CH2-CH2; as Polyquaternium 18, where r=s=3, q=7, t=1 R6, R7,R8 and R9 are methyl groups, and A is —CH2-CH2-O—CH2-CH2; as the blockcopolymer formed by the reaction of Polyquaternium-2 withPolyquaternium-17, which are known as Polyquaternium 27 (e.g. Mirapol175 by Rhodia).

8) Copolymers of vinylpyrrolidones and of vinylimidazoles and optionallyvinylcaprolactums, including polymers known as Polyquaternary-16 formedfrom methylvinylimidazolium chlorides and vinylpyrrolidones (e.g.Luviquat FC370//FC550/FC905/HM-552 by BASF); copolymers ofvinylcaprolactams and vinylpyrrolidones with methylvinylimidazoliummethosulfates, including polymers known as Polyquaternium-46 (e.g.Luviquat Hold by BASF); copolymers of vinylpyrrolidones and quaternizedimidazolines, including polymers known as polyquaternary 44 (e.g.Luviquat Care by BASF).

9) Polyamines such as Polyquart H sold by Cognis under the referencename polyethylene glycol (15) tallow polyamine.

10) Cross linked methacryloyloxy(C1-C4)alkyltri(C1-C4)alkylammonium saltpolymers such as the polymers obtained by homopolymerisation ofdimethylaminoethyl methacrylates quaternized with methyl chloride, or bycopolymerisation of acrylamides with dimethylaminoethyl methacrylatesquaternized with methyl chloride, the homo or copolymerisation beingfollowed by crosslinking with a compound comprising olefinicunsaturation, such as methylenebisacrylamides, including polymers knownas Polyquaternium-37 (e.g. Synthalen CN/CR/CU sold by 3V sigma; or as adispersion in another media such as Salcare SC95/SC96 by Ciba; RheocareCTH(E) by Cosmetic Rheologies) and polymers known as Polyquaternium-32(e.g. sold as a dispersion in mineral oil such as Salcare SC92 by Ciba).

11) Further examples of cationic polymers include polymers known asPolyquaternium 51 (e.g. Lipidure-PMB by NOF), as Polyquaternium 54 (e.g.Qualty-Hy by Mitsui), as Polyquaternium 56 (e.g. Hairrol UC-4 by Sanyochemicals), as Polyquaternium 87 (e.g. Luviquat sensation by BASF).

12) Silicone polymers comprising cationic groups and/or groups which maybe ionised into cationic groups. Suitable examples include cationicsilicones of the general formula(R10-N+(CH3)2)-R11-(Si(CH3)2-O)x-R11-(N+(CH3)2)-R10), where R10 is analkyl derived from coconut oil, and R11 is (CH2CHOCH2O(CH2)3 and x is anumber between 20 and 2000, including polymers known as Quaternium 80(e.g. Abil Quat 3272/3474 sold by Goldschmidt); silicones containinggroups which may be ionised into cationic groups, for exampleaminosilicones containing at least 10 repeating siloxane —(Si(CH3)2-O)units within the polymer chain, with either terminal, graft or a mixtureof terminal and graft aminofunctional groups. Example functional groupsare not limited to aminoethylaminopropyl, aminoethylaminoisobutly,aminopropyl. In the case of graft polymers, the terminal siloxane unitscan either be (CH3)3Si—O or R12(CH3)₂Si—O, where R12 can be either OH orOR13, where R13 is a C1-C8 alky group, or a mixture of both functionalterminal groups. These silicones are also available as preformedemulsions. Polymer with terminal siloxane units of (CH3)3Si—O examplesincludes polymers known as trimethylsilylamodimethicone (e.g. DC-2-8566,DC 7224, DC-2-8220 by Dow Corning; SF1708, SM 2125 GE Silicones; WackerBelsil ADM 653 by Wacker silicones). Further examples include polymerswith terminal siloxane units of (R120)(CH3)2Si—O where R12 can be eitherOH or OR13, where R13 is a C1-C8 alky group, or a mixture of bothfunctional terminal groups, known as amodimethicone (e.g. Wacker BelsilADM 1100/ADM 1600/ADM 652/ADM 6057E/ADM 8020 by Wacker Silicones; DC929,DC939, DC949 by Dow Corning; SM2059 by GE silicones). Siliconescontaining groups which may be ionised into cationic groups—for examplesilicones containing at least 10 repeating siloxane —(Si(CH3)2-O) unitswithin the polymer chain, with either terminal, graft or a mixture ofterminal and graft aminofunctional groups, together with additionalfunctional groups. Additional functional groups can includepolyoxyalkylene, the reaction product of amines and carbinols, alkychains. For example products known as methoxy PEG/PPG-7/3 AminopropylDimethicone (e.g. Abil Soft AF100 by Degussa). For example productsknown as Bis (C13-15 Alkoxy) PG Amodimethicone (e.g. DC 8500 by DowCorning).

In an embodiment, the cationic polymer is selected from the groupconsisting of polyquaternium 37, polyquaternium 7, polyquaternium 22,polyquaternium 87, and mixtures thereof; alternatively from the groupconsisting of polyquaternium 37, polyquaternium 22, and mixturesthereof.

Surfactants

The hair color compositions described herein may further comprise asurfactant. Suitable surfactants generally have a lipophilic chainlength of from about 8 to about 30 carbon atoms and can be selected fromanionic surfactants, nonionic surfactants, amphoteric surfactants,cationic surfactants, and mixtures thereof.

In an embodiment, the hair color compositions may comprise a totalamount of surfactants ranging from about 0.01% to about 60%,alternatively from about 0.05% to about 30%, alternatively from about0.1% to about 25%, alternatively from about 0.1% to about 20%, by weightof the total composition.

The compositions may comprise a mixture of an anionic surfactant and anamphoteric surfactant with one or more nonionic surfactants. Thecomposition may comprise a total amount of anionic surfactant rangingfrom about 0.01% to about 20%, alternatively from about 0.05% to about15%, alternatively from about 0.1% to about 15%, by weight of the totalcomposition; and a total amount of amphoteric and/or nonioniccomponents, which may range independently from each other from about0.01% to about 15%, alternatively from about 0.05% to about 10%,alternatively from about 0.1% to about 8%, by weight of the totalcomposition.

Suitable anionic surfactants include, but are not limited to: salts(such as alkaline salts, for example, sodium salts, ammonium salts,amine salts, amino alcohol salts and magnesium salts) of the followingcompounds: alkyl sulphates, alkyl ether sulphates, alkylamido ethersulphates, alkylarylpolyether sulphates, monoglyceride sulphates; alkylsulphonates, alkyl phosphates, alkylamide sulphonates, alkylarylsulphonates, a-olefin sulphonates, paraffin sulphonates; alkylsulphosuccinates, alkyl ether sulphosuccinates, alkylamidesulphosuccinates; alkyl sulphosuccinamates; alkyl sulphoacetates; alkylether phosphates; acyl sarcosinates; acyl isethionates; N-acyltaurates;and mixtures thereof. The alkyl or acyl radical of all of these variouscompounds, for example, comprises from 8 to 24 carbon atoms, and thearyl radical, for example, is chosen from phenyl and benzyl groups.Among the anionic surfactants, which can also be used, mention may alsobe made of fatty acid salts such as the salts of oleic, ricinoleic,palmitic and stearic acids, coconut oil acid or hydrogenated coconut oilacid; acyl lactylates in which the acyl radical comprises from 8 to 20carbon atoms. Weakly anionic surfactants can also be used, such asalkyl-D-galactosiduronic acids and their salts, as well aspolyoxyalkylenated (C₆-C₂₄) alkyl ether carboxylic acids,polyoxyalkylenated (C₆-C₂₄) alkylaryl ether carboxylic acids,polyoxyalkylenated (C₆-C₂₄) alkylamido ether carboxylic acids and theirsalts, for example, those comprising from 2 to 50 ethylene oxide groups,and mixtures thereof. Anionic derivatives of polysaccharides, forexample carboxyalkyl ether of alkyl polyglucosides, can be also used.

Nonionic surfactants are compounds that are well known (see, forexample, in this respect “Handbook of Surfactants” by M. R. Porter,published by Blackie & Son (Glasgow and London), 1991, pp. 116-178).Suitable non-ionic surfactants include, but are not limited to:polyethoxylated, polypropoxylated and polyglycerolated fatty acids,alkyl phenols, α-diols and alcohols comprising a fatty chain comprising,for example, from 8 to 18 carbon atoms, it being possible for the numberof ethylene oxide or propylene oxide groups to range, for example, from2 to 200 and for the number of glycerol groups to range, for example,from 2 to 30. Mention may also be made of copolymers of ethylene oxideand of propylene oxide, condensates of ethylene oxide and of propyleneoxide with fatty alcohols; polyethoxylated fatty amides preferablyhaving from 2 to 30 mol of ethylene oxide and their momoethanolamine anddiethanolamine derivatives, polyglycerolated fatty amides, for example,comprising on average from 1 to 5, and such as from 1.5 to 4, glycerolgroups; polyethoxylated fatty amines such as those containing from 2 to30 mol of ethylene oxide; oxyethylenated fatty acid esters of sorbitanhaving from 2 to 30 mol of ethylene oxide; fatty acid esters of sucrose,fatty acid esters of polyethylene glycol, alkylpolyglycosides,N-alkylglucamine derivatives, amine oxides such as (C₁₀-C₁₄)alkylamineoxides or N-acylaminopropylmorpholine oxides.

Suitable amphoteric surfactants include, but are not limited to:aliphatic secondary and tertiary amine derivatives in which thealiphatic radical is chosen from linear and branched chains comprisingfrom 8 to 22 carbon atoms and comprising at least one water-solubleanionic group (for example carboxylate, sulphonate, sulphate, phosphateor phosphonate); mention may also be made of (C₈-C₂₀)alkylbetaines,sulphobetaines, (C₈-C₂₀)alkylamido(C₁-C₆)alkylbetaines or(C₈-C₂₀)alkylamido(C₁-C₆)alkylsulphobetaines. Among the aminederivatives, mention may be made of the products sold as Miranol, asdescribed, for example, in U.S. Pat. Nos. 2,528,378 and 2,781,354 andhaving the structures of: R₂—CONHCH₂CH₂—N+(R₃)(R₄)(CH₂COO⁻), (XIX) inwhich: R₂ is chosen from alkyl radicals derived from an acid R₂—COOHpresent in hydrolysed coconut oil, and heptyl, nonyl and undecylradicals, R₃ is a β-hydroxyethyl group and R₄ is a carboxymethyl group;and of R₅—CONHCH₂CH₂—N(B)(C) (XX) wherein B represents —CH₂CH₂OX′, Crepresents —(CH₂)_(z)—Y′, with z=1 or 2, X′ is chosen from the—CH₂CH₂—COOH group and a hydrogen atom, Y′ is chosen from —COOH and—CH₂—CHOH—SO₃H radicals, R₅ is chosen from alkyl radicals of an acidR₅—COOH present in coconut oil or in hydrolysed linseed oil, alkylradicals, such as C₇, C₉, C₁₁ and C₁₃ alkyl radicals, a C₁₇ alkylradical and its iso form, and unsaturated C₁₇ radical. These compoundsare classified in the CTFA dictionary, 5^(th) edition, 1993, under thenames disodium cocoamphodiacetate, disodium lauroamphodiacetate,disodium caprylamphodiacetate, disodium capryloamphodiacetate, disodiumcocoamphodipropionate, disodium lauroamphodipropionate, disodiumcaprylamphodipropionate, disodium capryloamphodipropionate,lauroamphodipropionic acid, and cocoamphodipropionic acid. Salts ofdiethyl aminopropyl cocoaspartamid can be also used.

Suitable cationic surfactants include, but are not limited to, thequaternary ammonium salts A) to D) as defined hereinafter:

A) Quaternary ammonium salts of general formula (XXI) below:

wherein X⁻ is an anion chosen from halides (chloride, bromide andiodide), (C₂-C₆)alkyl sulphates, such as methyl sulphate, phosphates,alkyl and alkylaryl sulphonates, and anions derived from organic acids,such as acetate and lactate, and wherein R₁ to R₄ are as below in i) orii).

i) Radicals R₁ to R₃, which may be identical or different, are chosenfrom linear and branched aliphatic radicals comprising from 1 to 4carbon atoms, and aromatic radicals such as aryl and alkylaryl. Thealiphatic radicals may comprise at least one hetero atom such as oxygen,nitrogen, sulphur and halogens. The aliphatic radicals may be chosenfrom: alkyl, alkoxy and alkylamide radicals. R₄ is chosen from linearand branched alkyl radicals comprising from 16 to 30 carbon atoms. Asuitable cationic surfactant is, for example, a behenyltrimethylammoniumsalt (for example chloride).

ii) Radicals R₁ and R₂, which may be identical or different, are chosenfrom linear and branched aliphatic radicals comprising from 1 to 4carbon atoms, and aromatic radicals such as aryl and alkylaryl. Thealiphatic radicals may comprise at least one hetero atom such as oxygen,nitrogen, sulphur and halogens. The aliphatic radicals may be chosenfrom alkyl, alkoxy, alkylamide and hydroxyalkyl radicals comprising fromabout 1 to 4 carbon atoms. Radicals R₃ and R₄, which may be identical ordifferent, are chosen from linear and branched alkyl radicals comprisingfrom 12 to 30 carbon atoms, the said alkyl radicals comprise at leastone function chosen from ester and amide functions. R₃ and R₄ may bechosen from (C₁₂-C₂₂)alkylamido(C₂-C₆)alkyl and (C₁₂-C₂₂) alkylacetateradicals. A suitable cationic surfactant is, for example, adicetyldimethyl ammonium salt (for example chloride);

B) Quaternary ammonium salts of imidazolinium of formula (XXII) below:

in which R₅ is chosen from alkenyl and alkyl radicals comprising from 8to 30 carbon atoms, for example fatty acid derivatives of tallow, R₆ ischosen from a hydrogen atom, C₁-C₄ alkyl radicals and alkenyl and alkylradicals comprising from 8 to 30 carbon atoms, R₇ is chosen from C₁-C₄alkyl radicals, R₈ is chosen from a hydrogen atom and C₁-C₄ alkylradicals, and X⁻ is an anion chosen from halides, phosphates, acetates,lactates, alkyl sulphates, alkyl sulphonates and alkylaryl sulphonates.In one embodiment, R₅ and R₆ are, for example, a mixture of radicalschosen from alkenyl and alkyl radicals comprising from 12 to 21 carbonatoms, such as fatty acid derivatives of tallow, R₇ is methyl and R₈ ishydrogen. Such a product is, for example, Quaternium-27 (CTFA 1997) orQuaternium-83 (CTFA 1997), commercially available as “Rewoquat®”W75/W90/W75PG/W75HPG by Witco.

C) Diquaternary ammonium salts of formula (XXIII):

in which R₉ is chosen from aliphatic radicals comprising from about 16to 30 carbon atoms, R₁₀, R₁₁, R₁₂, R₁₃ and R₁₄, which may be identicalor different, are chosen from hydrogen and alkyl radicals comprisingfrom 1 to 4 carbon atoms, and X⁻ is an anion chosen from halides,acetates, phosphates, nitrates and methyl sulphates. Such diquaternaryammonium salts, for example, include propanetallowdiammonium dichloride.

D) Quaternary ammonium salts comprising at least one ester function, offormula (XXIV) below:

in which: R15 is chosen from C1-C6 alkyl radicals and C1-C6 hydroxyalkyland dihydroxyalkyl radicals; R16 is chosen from: a radical R19C(O)—,linear and branched, saturated and unsaturated C1-C22 hydrocarbon-basedradicals R20, and a hydrogen atom, R18 is chosen from: a radicalR21C(O)—, linear and branched, saturated and unsaturated C1-C6hydrocarbon-based radicals R22, and a hydrogen atom, R17, R19 and R21,which may be identical or different, are chosen from linear andbranched, saturated and unsaturated C7-C21 hydrocarbon-based radicals;n, p and r, which may be identical or different, are chosen fromintegers ranging from 2 to 6; y is chosen from integers ranging from 1to 10; x and z, which may be identical or different, are chosen fromintegers ranging from 0 to 10; X− is an anion chosen from simple andcomplex, organic and inorganic anions; with the proviso that the sumx+y+z is from 1 to 15, that when x is 0, then R16 is R20 and that when zis 0, then R18 is R22. In one embodiment, the ammonium salts of formula(XXXXI) can be used, in which: R15 is chosen from methyl and ethylradicals, x and y are equal to 1; z is equal to 0 or 1; n, p and r areequal to 2; R16 is chosen from: a radical R19C(O)—, methyl, ethyl andC14-C22 hydrocarbon-based radicals, and a hydrogen atom; R17, R19 andR21, which may be identical or different, are chosen from linear andbranched, saturated and unsaturated C7-C21, hydrocarbon-based radicals;R18 is chosen from: a radical R21C(O)— and a hydrogen atom. Suchcompounds are commercially available as Dehyquart by Cognis, Stepanquatby Stepan, Noxamium by Ceca, and Rewoquat WE 18 by Rewo-Witco.Data

Uptake and washfastness: The uptake total color change (ΔE¹) describeshow much the hair color has changed after white Piedmont hair strandssupplied by International Hair Importers & Products has been dyed. ΔE iscalculated as the square root of sum of squares of ΔL*, Δa* and Δb*. Thetotal color change for washfastness (ΔE²) is measured after the dyedhair switches are processed through a 12-cycle rinse study. One cycle isdefined as two shampoo treatments followed by a conditioning treatment.The hair switches are blow dried between each shampoo treatment. Colordata is collected after the hair is properly dried on a Minoltaspectrophotometer CM-3700d. Examples 1 through 11 are embodiments of thewashfast direct dye compounds described herein.

TABLE 1 Colorstrike and washfastness data on natural white hair fromimidazolium azo dyes. Compound Number Structure ΔE¹ ΔE² 1

56.35 6.22 2

59.27 5.78 3

59.98 5.47 4

60.05 5.31 5

60.38 6.16 6

56.35 9.45 7

58.26 5.78 8

58.64 3.55 9

60.84 6.8  10

62.41 3.89 11

60.66 6.27 ¹uptake on natural white virgin hair from water adjusted topH 10.8 with 28% ammonia, and this solution is mixed with an equalvolume of a 6% commercial hydrogen peroxide solution, such as ClairolProfessional ® Soy 4Plex Clairoxide ®. ²washfastness on natural whitevirgin hair using a commercial SLS shampoo.

The smaller the total color change (AE²) for washfastness after 24shampoos, the more washfast the dye is.

TABLE 2 On-tone fading data on virgin natural white hair after 24shampoos, measured as change in hue angle, for a shade made from bluedirect dye (E)-1,3-bis(3-ammoniopropyl)-2-((1,4-diethyl-1,2,3,4-tetrahydroquinoxalin-6-yl)diazenyl)-1H-imidazol-3-iumbromide dichloride) and a yellow direct dye of complementary structure((E)-2-((5-amino-1-hexyl-1H-pyrazol-4-yl)diazenyl)-1,3-bis(3-aminopropyl)-1H-imidazol-3-ium bromidedihydrochloride). Δh after a 12-cycle rinse - blonde virgin CompoundStructures Hair Type hair (E)-1,3-bis(3- ammoniopropyl)-2-((1,4-diethyl-1,2,3,4- tetrahydroquinoxalin- 6-yl)diazenyl)-1H-imidazol-3-ium bromide dichloride                            (E)-2-((5-amino-1- hexyl-1H-pyrazol-4- yl)diazenyl)-1,3-bis(3-aminopropyl)- 1H-imidazol-3-ium bromide dihydrochloride equimolar

Virgin Natural White                                       Bleached Yak−6.80                                         −3.96 Smaller the hueangle change (Δh) = better on-tone fading.

It is noted that terms like “preferably,” “usually”, “generally,”“commonly,” and “typically” are not utilized herein to limit the scopeof the claimed invention or to imply that certain features are critical,essential, or even important to the structure or function of the claimedinvention. Rather, these terms are merely intended to highlightalternative or additional features that may or may not be utilized in aparticular embodiment of the present invention.

For the purposes of describing and defining the present invention it isadditionally noted that the term “substantially” is utilized herein torepresent the inherent degree of uncertainty that may be attributed toany quantitative comparison, value, measurement, or otherrepresentation. The term “substantially” is also utilized herein torepresent the degree by which a quantitative representation may varyfrom a stated reference without resulting in a change in the basicfunction of the subject matter at issue.

Having described the invention in detail and by reference to specificembodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of theinvention defined in the appended claims. More specifically, althoughsome aspects of the present invention are identified herein as preferredor particularly advantageous, it is contemplated that the presentinvention is not necessarily limited to these preferred aspects of theinvention.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application and any patent application or patent to which thisapplication claims priority or benefit thereof, is hereby incorporatedherein by reference in its entirety unless expressly excluded orotherwise limited. The citation of any document is not an admission thatit is prior art with respect to any invention disclosed or claimedherein or that it alone, or in any combination with any other referenceor references, teaches, suggests or discloses any such invention.Further, to the extent that any meaning or definition of a term in thisdocument conflicts with any meaning or definition of the same term in adocument incorporated by reference, the meaning or definition assignedto that term in this document shall govern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made withoutdeparting from the spirit and scope of the invention. It is thereforeintended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A method of dyeing the hair, the methodcomprising: a. applying to the hair a hair color composition comprisingone or more direct dye compounds, the one or more direct dye compoundseach comprising: i. a yellow chromophore; ii. one or two permanentcations, wherein the permanent cations are pendant to the chromophore orpart of the chromophore, and wherein the chromophore and the permanentcations form a core structure; and iii. one to four incipient cations,wherein each of the one to four incipient cations is pendant via alinker group to the core structure, and wherein the incipient cationsare neutral; iv. one or more C2-C9 hydrophobic moieties, wherein the oneor more C2-C9 hydrophobic moieties are pendant to the core structure;wherein the one or more direct dye compounds enter the hair shaft afterthe hair color composition is applied to the hair; and  wherein the haircolor composition has a pH of from about 6 to about 11; b. rinsing thehair with water;  wherein the pH of the hair after rinsing is from about3.5 to about 6; and  wherein the rinsing of the hair causes one or moreof the one to four incipient cations to change from neutral topositively charged inside of the hair shaft, wherein the yellowchromophore has a structure according to Formula V or a tautomer or saltthereof:

wherein (i) R_(1b), R_(1c), and R_(1f) are each independently hydrogen,alkyl, halogen substituted alkyl, alkenyl, alkynyl, aryl, hydroxyalkyl,aminoalkyl, alkyl group carrying a quaternary ammonium cation, alkoxy,aryloxy, acyl, halogen, a heterocyclic moiety, thioether, thiol with alinker group, alkylsulfonate, alkylsulfate, carboxylalkyl, acrylamide orsubstituted acrylamides with a linker group, vinylsulfone with a linkergroup, sulfonyl ethyl sulfate with a linker group, halo-s-triazines witha linker group, halopyrimidines with a linker group, or haloquinoxalineswith a linker group; (ii) R_(1a), R_(1d), and R_(1h) are eachindependently hydrogen, alkyl, halogen substituted alkyl, alkenyl,alkynyl, aryl, hydroxyalkyl, aminoalkyl, alkyl group carrying aquaternary ammonium cation, a heterocyclic moiety, thiol with a linkergroup, alkylsulfonate, alkylsulfate, carboxylalkyl, acrylamide orsubstituted acrylamides with a linker group, vinylsulfone with a linkergroup, sulfonyl ethyl sulfate with a linker group, halo-s-triazines witha linker group, halopyrimidines with a linker group, or haloquinoxalineswith a linker group; and (iii) R_(1e) and R_(1g) are each independentlyhydrogen, alkyl, halogen substituted alkyl, alkenyl, alkynyl, aryl,hydroxyalkyl, aminoalkyl, alkyl group carrying a quaternary ammoniumcation, a heterocyclic moiety, thiol with a linker group,alkylsulfonate, alkylsulfate, carboxylalkyl, acrylamide or substitutedacrylamides with a linker group, vinylsulfone with a linker group,sulfonyl ethyl sulfate with a linker group, halo-s-triazines with alinker group, halopyrimidines with a linker group, or haloquinoxalineswith a linker group, or are attached to a polymer backbone through alinker, or part of a cyclic structure and joined by substituted orunsubstituted alkyl or heteroalkyl groups.
 2. The method of claim 1,wherein the one or more direct dye compounds each comprise two incipientcations.
 3. The method of claim 1, wherein the one or more direct dyecompounds each has a molecular weight of less than about 1,000 g/mol. 4.The method of claim 1, wherein the hair color composition has a pH offrom about 9 to about
 11. 5. The method of claim 1, wherein the haircolor composition has a pH of from about 6 to about
 9. 6. The method ofclaim 1, wherein an oxidizing agent is applied before or during theapplication of the hair color composition.
 7. The method of claim 6,wherein the oxidizing agent is selected from the group consisting ofperoxides, perborates, percarbonates, persulfates, oxidant generatingenzymes, oxidant generating substrates, and combinations thereof.
 8. Themethod of claim 1, wherein the hair color composition further comprisesone or more oxidation dyes.
 9. The method of claim 1, wherein the haircolor composition comprises at least one oxidation dye primaryintermediate.
 10. The method of claim 1, wherein the hair colorcomposition comprises at least one oxidation dye coupler.
 11. The methodof claim 1, wherein the hair color composition further comprises atleast 20%, by weight of the composition, water.
 12. The method of claim1, wherein the hair color composition further comprises from about 0.1%to about 20%, by weight of the composition, of at least one oxidizingagent.
 13. The method of claim 1, wherein the hair color composition hasa pH of from about 7 to about 11.